Don't even get me started on what is wrong with IE! We currently have web compliant standards for cross-integration. This means that if the code is compliant it will be cross-compatible in different browsers - Internet explorer is the exception and makes it very difficult to write code for every browser. (Microsoft doesn't care) ...I said don't get me started...
For some help with this and common hacks to some of the common problems, check here:
http://www.howtocreate.co.uk/wrongWithIE/
you should be able to find help with most problems there. If you need more I can post more links, I have lots...