I'm not sure where you're adding your code by try the following:
<?php
$doc = JFactory::getDocument();
$doc->addScriptDeclaration('
jQuery(document).ready(function($) {
$(".social-button").attr("target","_blank");
});
');
?>
The above code uses Jooma API methods to inject your code in the <head>
of your template.
I'm not sure how you're importing jQuery or if this is already being done. If you are importing jQuery yourself, then please read my answer on How to import jQuery in Joomla as it might be possible that you have multiple libraries being loaded and thus causing conflicts.
And finally on a side note, Joomla does, like any CMS out there have it's down side, but for an out-the-box CMS it's actually very good and extremely flexible. If you were to upgrade to 3.3.1, you will find even more features at the palm of your hand.