OK, things are looking alright to me. I checked on Firefox5 and IE8 and IE9.
There were a few js scripts being called in and I'm not sure what they were to:
<script type="text/javascript" src="/plugins/system/2j_tabs/jq_last.js"></script>
<script type="text/javascript" src="/plugins/system/2j_tabs/2j.ui.base.js"></script>
<script type="text/javascript" src="/plugins/system/2j_tabs/2j.ui.tabs.js"></script>
If something is causing an issue, in IE especially, try disabling whatever this feature is and refresh.
I also didn't notice any sidebar modules on the site, so not sure if you pulled those down so it wouldn't appear broken or not.
If you're seeing sidebars pushed to the bottom, it's usually one of two things...
Not enough room for them. So changing padding and margins and widths could have squeezed them out.
or
A missing or out of place closing div container tag. I didn't see any broken div tag issues when checking validation, so you may want to see about padding and margin issues. Also, some browsers calculate this different, so it may appear fine in Firefox but broken in IE. If that's the case, let us know so we can check in the browser it's broken.