Joomla Layout Issue in IE7, not IE8, GC or FF!

Hi, I'm building a new Joomla site for our school, having moved away from our custom Moodle due to county decisions.

The site is http://www.marneljuniors.com. In IE7, the middle section doesn't start until the end of left column, so there is a load of blank space in the middle of the page. Upgraded to IE8, all is fine. Tested in Chrome and FF3.5, all ok. Interestingly, in IE8 with compatability mode on, it gives the same problems as with IE7.

The template is the default one shipped with Joomla (latest version), with white colour option.

Any thoughts? I've looked around the web for hours, but can't find anything. Have also used Chrome inspetor and Firebug and IEDom inspector, but I'm not a CSS guru, which is what I suspect this is!

Any help greatly appreciate- thanks!

Bump! Ant thoughts?

Turns out that IE7 is rubbish. I ended up using a different template which is quite similar. NOt as nice, but beats going through every detail of css / div tags and working it out.