Page stops loading

Site in question: http://www.blueopia.com
Template: Water3 1.0 (From: themes.wordpress.net)

Im having quite an odd problem. I am running 2.1.2 as of a few minutes ago, but I was running 2.1 from february until today. The problem started before I updated, and continues after I updated.

The problem is that at random, the page stops loading. You can see now, although it may be one of the times when the page loads. Heres a screenshot just in case:
http://www.blueopia.com/images/broke.png

It was loading fine when I installed this template today, and had not seen this before. I looked around and went to class. When I got home a few hours later, I loaded up the site just fine, logged in and started adding categories. Thats when I saw it the first time, although after a few refreshes it worked again. So I made a test post to check how blockquote looked, and it appeared again. I thought it might just be me, but my friend also gets the same error. The error log is empty.

Heres the code at that point it breaks:

[code]

<li id="search"><h2>Search</h2>
<form method="get" id="searchform" action="<?php echo $_SERVER['PHP_SELF']; ?>">
<div>
<input type="text" value="<?php echo wp_specialchars($s, 1); ?>" name="s" id="s" />
</div>
</form>

[/code]

Any help would be appreciated. I had not edited any code in the file where that appears, and have only modified header.php to remove a line of text, and footer.php to add some text.