Hi Bryan,
I haven't checked your site in IE 8 yet but checking it with Chrome I see a few problems worth pointing out.
The images load noticeably slow on a first visit because they are very large.
2010arcover.png is 409KB and fp_background3.png is 575KB, adding up to almost 1 MB just for those 2 images. and then you have those slide images in addition to that so the payload size of your page is really pretty large.
My first advice is to optimize all of those images and reduce their size as much as you can.
Next I also notice that you are loading jquery twice because it is already loaded by mojoPortal and you have custom code loading a different version. You should eliminate that code and just use the version loaded by mojoportal. If you need a specific version you can control it from web.config settings.
That could be a factor in the IE 8 problem as could the image sizes.
Next when I view the source of your page I see a bunch of xml garbage that shows the content was pasted from Word. I "think" using the Paste From Word toolbar item in the editor is supposed to clean that junk out but maybe you did not use that toolbar. In any case you will see it if you view the source of the page or use source view in the editor and you should clean that out because it is a lot of extra text and also adds to the payload size of the page.
If the problem persists after following those suggestions let me know and I'll take a look with IE 8, but I have a feeling these suggestions would improve things.
Hope that helps,
Joe