What's wrong with my CSS? (IE Problem)

[curtiss]

Can someone take a look at http://dchelp.net/dcevotest/ and see what I might have missed in my CSS? The site looks almost exactly the way I want it in Firefox, but my main content box is way too wide in IE (it appears that something, somewhere, is causing the main content box to be 100% of the screen width, even though I have the width set to "auto").

I don't want a fixed-width layout, so I kind of have to use the "auto" attribute. I'm not sure if I'm just overlooking some spot where I accidentally set the width on something to 100%, or if there's some CSS-bug in IE that's screwing it up.

In addition, the padding on my "Active Forum Topics" list seems to be a bit off in IE, but I'll probably try to tackle that problem later.

[curtiss]

I've moved the site to http://dev.dcevolution.net/ but I'm still having the same problem with IE. The site looks exactly the way I want it in Firefox and Opera (it actually looks really good on the Nintendo Wii), but it looks abysmal in Internet Explorer because the main content box is stretching to 100% of the inner width for some reason, which means that it runs underneath the right menu, and causes the user to have to scroll 200 pixels to the right in order to see the whole thing.

Does anyone see anything in my CSS or my HTML that may be causing the problem? It's really grating on my nerves.

EDIT - Also, if you look at the site in both Firefox and IE, you will notice that my "Active Forum Topics" list is a bit off in IE as well. Any suggestions on that?