Looks much better now.. still a couple of alignment issues, but it looks like you're figuring it out.
The "Works in IE but not in FF" (and visa versa) thing is really a never ending battle. The best thing I did to help it was learn XHTML and have really clean code. Helped out a ton. If you're using a WYSIWYG HTML editor, that may be part of the problem as well..
Now where it really gets tricky: Making vBulletin all CSS / tableless.. and still making it function in both IE and FF..