I'm not sure this is the best fix, but it should accomplish what you're after anyway.
In the HTML file, change this portion:
Code:
</span>
<!-- End Editable Content-->
<br /><br />
</div>
To:
Code:
</span>
<!-- End Editable Content-->
<br /><br />
<div style="clear:both;"></div>
</div>
Basically adding
<div style="clear:both;"></div> below the two <br /> tags.
Here's the same page with that change applied (hosted off my temp server):
Meh626 DIV Stretching Help!