It is something we are currently working on as we realis the current loading of Google fonts is far from ideal!
In the meantime you can try replacing the following in your templates styles.php (..templates/j51_classic/php/styles/php)....
<?php /*?>Set Google font choices to body, articleheads, moduleheads and hornav menu<?php */?>
<?php if(($body_fontstyle == "Arial, Helvetica, sans-serif") || ($body_fontstyle == "Courier, monospace") || ($body_fontstyle == "Tahoma, Geneva, sans-serif") || ($body_fontstyle == "Garamond, serif") || ($body_fontstyle == "Georgia, serif") || ($body_fontstyle == "Impact, Charcoal, sans-serif") || ($body_fontstyle == "Lucida Console, Monaco, monospace") || ($body_fontstyle == "Lucida Sans Unicode, Lucida Grande, sans-serif") || ($body_fontstyle == "MS Sans Serif, Geneva, sans-serif") || ($body_fontstyle == "MS Serif, New York, sans-serif") || ($body_fontstyle == "Palatino Linotype, Book Antiqua, Palatino, serif") || ($body_fontstyle == "Times New Roman, Times, serif") || ($body_fontstyle == "Trebuchet MS, Helvetica, sans-serif") || ($body_fontstyle == "Verdana, Geneva, sans-serif")) : ?>
<style type="text/css">body, input, button, select, textarea {font-family:<?php echo str_replace("+"," ",$body_fontstyle); ?> }</style>
<?php elseif(($body_fontstyle != "Arial, Helvetica, sans-serif") || ($body_fontstyle != "Courier, monospace") || ($body_fontstyle != "Tahoma, Geneva, sans-serif") || ($body_fontstyle != "Garamond, serif") || ($body_fontstyle != "Georgia, serif") || ($body_fontstyle != "Impact, Charcoal, sans-serif") || ($body_fontstyle != "Lucida Console, Monaco, monospace") || ($body_fontstyle != "Lucida Sans Unicode, Lucida Grande, sans-serif") || ($body_fontstyle != "MS Sans Serif, Geneva, sans-serif") || ($body_fontstyle != "MS Serif, New York, sans-serif") || ($body_fontstyle != "Palatino Linotype, Book Antiqua, Palatino, serif") || ($body_fontstyle != "Times New Roman, Times, serif") || ($body_fontstyle != "Trebuchet MS, Helvetica, sans-serif") || ($body_fontstyle != "Verdana, Geneva, sans-serif")) : ?>
<link rel="stylesheet" type="text/css" href="http://fonts.googleapis.com/css?family=<?php echo $body_fontstyle ?>:300,400" />
<style type="text/css">body, input, button, select, textarea {font-family:<?php echo str_replace("+"," ",$body_fontstyle); ?> }</style>
<?php endif; ?>
<?php if(($h1head_fontstyle == "Arial, Helvetica, sans-serif") || ($h1head_fontstyle == "Courier, monospace") || ($h1head_fontstyle == "Tahoma, Geneva, sans-serif") || ($h1head_fontstyle == "Garamond, serif") || ($h1head_fontstyle == "Georgia, serif") || ($h1head_fontstyle == "Impact, Charcoal, sans-serif") || ($h1head_fontstyle == "Lucida Console, Monaco, monospace") || ($h1head_fontstyle == "Lucida Sans Unicode, Lucida Grande, sans-serif") || ($h1head_fontstyle == "MS Sans Serif, Geneva, sans-serif") || ($h1head_fontstyle == "MS Serif, New York, sans-serif") || ($h1head_fontstyle == "Palatino Linotype, Book Antiqua, Palatino, serif") || ($h1head_fontstyle == "Times New Roman, Times, serif") || ($h1head_fontstyle == "Trebuchet MS, Helvetica, sans-serif") || ($h1head_fontstyle == "Verdana, Geneva, sans-serif")) : ?>
<style type="text/css">h1{font-family:<?php echo str_replace("+"," ",$articlehead_fontstyle); ?> }</style>
<?php elseif(($h1head_fontstyle != "Arial, Helvetica, sans-serif") || ($h1head_fontstyle != "Courier, monospace") || ($h1head_fontstyle != "Tahoma, Geneva, sans-serif") || ($h1head_fontstyle != "Garamond, serif") || ($h1head_fontstyle != "Georgia, serif") || ($h1head_fontstyle != "Impact, Charcoal, sans-serif") || ($h1head_fontstyle != "Lucida Console, Monaco, monospace") || ($h1head_fontstyle != "Lucida Sans Unicode, Lucida Grande, sans-serif") || ($h1head_fontstyle != "MS Sans Serif, Geneva, sans-serif") || ($h1head_fontstyle != "MS Serif, New York, sans-serif") || ($h1head_fontstyle != "Palatino Linotype, Book Antiqua, Palatino, serif") || ($h1head_fontstyle != "Times New Roman, Times, serif") || ($h1head_fontstyle != "Trebuchet MS, Helvetica, sans-serif") || ($h1head_fontstyle != "Verdana, Geneva, sans-serif")) : ?>
<link rel="stylesheet" type="text/css" href="http://fonts.googleapis.com/css?family=<?php echo $articlehead_fontstyle ?>:100,400" />
<style type="text/css">h1{font-family:<?php echo str_replace("+"," ",$articlehead_fontstyle); ?>; }</style>
<?php endif; ?>
<?php if(($articlehead_fontstyle == "Arial, Helvetica, sans-serif") || ($articlehead_fontstyle == "Courier, monospace") || ($articlehead_fontstyle == "Tahoma, Geneva, sans-serif") || ($articlehead_fontstyle == "Garamond, serif") || ($articlehead_fontstyle == "Georgia, serif") || ($articlehead_fontstyle == "Impact, Charcoal, sans-serif") || ($articlehead_fontstyle == "Lucida Console, Monaco, monospace") || ($articlehead_fontstyle == "Lucida Sans Unicode, Lucida Grande, sans-serif") || ($articlehead_fontstyle == "MS Sans Serif, Geneva, sans-serif") || ($articlehead_fontstyle == "MS Serif, New York, sans-serif") || ($articlehead_fontstyle == "Palatino Linotype, Book Antiqua, Palatino, serif") || ($articlehead_fontstyle == "Times New Roman, Times, serif") || ($articlehead_fontstyle == "Trebuchet MS, Helvetica, sans-serif") || ($articlehead_fontstyle == "Verdana, Geneva, sans-serif")) : ?>
<style type="text/css">h2{font-family:<?php echo str_replace("+"," ",$articlehead_fontstyle); ?> }</style>
<?php elseif(($articlehead_fontstyle != "Arial, Helvetica, sans-serif") || ($articlehead_fontstyle != "Courier, monospace") || ($articlehead_fontstyle != "Tahoma, Geneva, sans-serif") || ($articlehead_fontstyle != "Garamond, serif") || ($articlehead_fontstyle != "Georgia, serif") || ($articlehead_fontstyle != "Impact, Charcoal, sans-serif") || ($articlehead_fontstyle != "Lucida Console, Monaco, monospace") || ($articlehead_fontstyle != "Lucida Sans Unicode, Lucida Grande, sans-serif") || ($articlehead_fontstyle != "MS Sans Serif, Geneva, sans-serif") || ($articlehead_fontstyle != "MS Serif, New York, sans-serif") || ($articlehead_fontstyle != "Palatino Linotype, Book Antiqua, Palatino, serif") || ($articlehead_fontstyle != "Times New Roman, Times, serif") || ($articlehead_fontstyle != "Trebuchet MS, Helvetica, sans-serif") || ($articlehead_fontstyle != "Verdana, Geneva, sans-serif")) : ?>
<link rel="stylesheet" type="text/css" href="http://fonts.googleapis.com/css?family=<?php echo $articlehead_fontstyle ?>:100,400" />
<style type="text/css">h2{font-family:<?php echo str_replace("+"," ",$articlehead_fontstyle); ?>; }</style>
<?php endif; ?>
<?php if(($modulehead_fontstyle == "Arial, Helvetica, sans-serif") || ($modulehead_fontstyle == "Courier, monospace") || ($modulehead_fontstyle == "Tahoma, Geneva, sans-serif") || ($modulehead_fontstyle == "Garamond, serif") || ($modulehead_fontstyle == "Georgia, serif") || ($modulehead_fontstyle == "Impact, Charcoal, sans-serif") || ($modulehead_fontstyle == "Lucida Console, Monaco, monospace") || ($modulehead_fontstyle == "Lucida Sans Unicode, Lucida Grande, sans-serif") || ($modulehead_fontstyle == "MS Sans Serif, Geneva, sans-serif") || ($modulehead_fontstyle == "MS Serif, New York, sans-serif") || ($modulehead_fontstyle == "Palatino Linotype, Book Antiqua, Palatino, serif") || ($modulehead_fontstyle == "Times New Roman, Times, serif") || ($modulehead_fontstyle == "Trebuchet MS, Helvetica, sans-serif") || ($modulehead_fontstyle == "Verdana, Geneva, sans-serif")) : ?>
<style type="text/css">.module h3, .module_menu h3{font-family:<?php echo str_replace("+"," ",$modulehead_fontstyle); ?>; }</style>
<?php elseif(($modulehead_fontstyle != "Arial, Helvetica, sans-serif") || ($modulehead_fontstyle != "Courier, monospace") || ($modulehead_fontstyle != "Tahoma, Geneva, sans-serif") || ($modulehead_fontstyle != "Garamond, serif") || ($modulehead_fontstyle != "Georgia, serif") || ($modulehead_fontstyle != "Impact, Charcoal, sans-serif") || ($modulehead_fontstyle != "Lucida Console, Monaco, monospace") || ($modulehead_fontstyle != "Lucida Sans Unicode, Lucida Grande, sans-serif") || ($modulehead_fontstyle != "MS Sans Serif, Geneva, sans-serif") || ($modulehead_fontstyle != "MS Serif, New York, sans-serif") || ($modulehead_fontstyle != "Palatino Linotype, Book Antiqua, Palatino, serif") || ($modulehead_fontstyle != "Times New Roman, Times, serif") || ($modulehead_fontstyle != "Trebuchet MS, Helvetica, sans-serif") || ($modulehead_fontstyle != "Verdana, Geneva, sans-serif")) : ?>
<link rel="stylesheet" type="text/css" href="http://fonts.googleapis.com/css?family=<?php echo $modulehead_fontstyle ?>:300,400,800" />
<style type="text/css">.module h3, .module_menu h3{font-family:<?php echo str_replace("+"," ",$modulehead_fontstyle); ?> }</style>
<?php endif; ?>
<?php if(($hornav_fontstyle == "Arial, Helvetica, sans-serif") || ($hornav_fontstyle == "Courier, monospace") || ($hornav_fontstyle == "Tahoma, Geneva, sans-serif") || ($hornav_fontstyle == "Garamond, serif") || ($hornav_fontstyle == "Georgia, serif") || ($hornav_fontstyle == "Impact, Charcoal, sans-serif") || ($hornav_fontstyle == "Lucida Console, Monaco, monospace") || ($hornav_fontstyle == "Lucida Sans Unicode, Lucida Grande, sans-serif") || ($hornav_fontstyle == "MS Sans Serif, Geneva, sans-serif") || ($hornav_fontstyle == "MS Serif, New York, sans-serif") || ($hornav_fontstyle == "Palatino Linotype, Book Antiqua, Palatino, serif") || ($hornav_fontstyle == "Times New Roman, Times, serif") || ($hornav_fontstyle == "Trebuchet MS, Helvetica, sans-serif") || ($hornav_fontstyle == "Verdana, Geneva, sans-serif")) : ?>
<style type="text/css">.hornav{font-family:<?php echo str_replace("+"," ",$hornav_fontstyle); ?> }</style>
<?php elseif(($hornav_fontstyle != "Arial, Helvetica, sans-serif") || ($hornav_fontstyle != "Courier, monospace") || ($hornav_fontstyle != "Tahoma, Geneva, sans-serif") || ($hornav_fontstyle != "Garamond, serif") || ($hornav_fontstyle != "Georgia, serif") || ($hornav_fontstyle != "Impact, Charcoal, sans-serif") || ($hornav_fontstyle != "Lucida Console, Monaco, monospace") || ($hornav_fontstyle != "Lucida Sans Unicode, Lucida Grande, sans-serif") || ($hornav_fontstyle != "MS Sans Serif, Geneva, sans-serif") || ($hornav_fontstyle != "MS Serif, New York, sans-serif") || ($hornav_fontstyle != "Palatino Linotype, Book Antiqua, Palatino, serif") || ($hornav_fontstyle != "Times New Roman, Times, serif") || ($hornav_fontstyle != "Trebuchet MS, Helvetica, sans-serif") || ($hornav_fontstyle != "Verdana, Geneva, sans-serif")) : ?>
<link rel="stylesheet" type="text/css" href="http://fonts.googleapis.com/css?family=<?php echo $hornav_fontstyle ?>:600,400,300" />
<style type="text/css">.hornav{font-family:<?php echo str_replace("+"," ",$hornav_fontstyle); ?> }</style>
<?php endif; ?>
<?php if(($logo_fontstyle == "Arial, Helvetica, sans-serif") || ($logo_fontstyle == "Courier, monospace") || ($logo_fontstyle == "Tahoma, Geneva, sans-serif") || ($logo_fontstyle == "Garamond, serif") || ($logo_fontstyle == "Georgia, serif") || ($logo_fontstyle == "Impact, Charcoal, sans-serif") || ($logo_fontstyle == "Lucida Console, Monaco, monospace") || ($logo_fontstyle == "Lucida Sans Unicode, Lucida Grande, sans-serif") || ($logo_fontstyle == "MS Sans Serif, Geneva, sans-serif") || ($logo_fontstyle == "MS Serif, New York, sans-serif") || ($logo_fontstyle == "Palatino Linotype, Book Antiqua, Palatino, serif") || ($logo_fontstyle == "Times New Roman, Times, serif") || ($logo_fontstyle == "Trebuchet MS, Helvetica, sans-serif") || ($logo_fontstyle == "Verdana, Geneva, sans-serif")) : ?>
<style type="text/css">h1.logo-text a{font-family:<?php echo str_replace("+"," ",$logo_fontstyle); ?> }</style>
<?php elseif(($logo_fontstyle != "Arial, Helvetica, sans-serif") || ($logo_fontstyle != "Courier, monospace") || ($logo_fontstyle != "Tahoma, Geneva, sans-serif") || ($logo_fontstyle != "Garamond, serif") || ($logo_fontstyle != "Georgia, serif") || ($logo_fontstyle != "Impact, Charcoal, sans-serif") || ($logo_fontstyle != "Lucida Console, Monaco, monospace") || ($logo_fontstyle != "Lucida Sans Unicode, Lucida Grande, sans-serif") || ($logo_fontstyle != "MS Sans Serif, Geneva, sans-serif") || ($logo_fontstyle != "MS Serif, New York, sans-serif") || ($logo_fontstyle != "Palatino Linotype, Book Antiqua, Palatino, serif") || ($logo_fontstyle != "Times New Roman, Times, serif") || ($logo_fontstyle != "Trebuchet MS, Helvetica, sans-serif") || ($logo_fontstyle != "Verdana, Geneva, sans-serif")) : ?>
<link rel="stylesheet" type="text/css" href="http://fonts.googleapis.com/css?family=<?php echo $logo_fontstyle ?>:300,400" />
<style type="text/css">h1.logo-text a{font-family:<?php echo str_replace("+"," ",$logo_fontstyle); ?> }</style>
<?php endif; ?>
<?php /*?>End Set Google font choices to body, articleheads, moduleheads and hornav menu<?php */?>
With the following... (edit to taste)..
<link href='http://fonts.googleapis.com/css?family=Lato:400,300' rel='stylesheet' type='text/css'>
<link href='http://fonts.googleapis.com/css?family=Raleway:400,300' rel='stylesheet' type='text/css'>
<style type="text/css">
/* Body */
body, input, button, select, textarea {font-family: 'Raleway', sans-serif; }
/* Article Title */
h2 {font-family: 'Lato', sans-serif; }
/* Module Title */
.module h3, .module_menu h3 {font-family: 'Lato', sans-serif; }
/* Top Menu */
.hornav {font-family: 'Lato', sans-serif; }
/* Logo Font */
h1.logo-text a {font-family: 'Lato', sans-serif; }
</style>
Ciarán