You can install IE on linux: http://www.psychocats.net/ubuntu/ies4linux
However unless it's critical you see what sites look like on old versions of IE or you have to regularly visit websites that have been written in the worst way possible, I'd steer clear!
Linux isn't great for gaming, but it's good for about everything else and does a heck of a lot WAY better than windows does. Pretty much everything gets installed via a package manager so you can upgrade everything on your system with a single click. Windows has nothing like that on the roadmap. Creating a server and don't want anything graphical to start up unless you ask it to (to save resources?) no problem. Think aeroglass looks good? Wait until you see compiz. Oh, and there's no pointless rebooting every few seconds, the file systems are all self defragmenting (catch up Microsoft) and these days, driver support is pretty damn good. And in linux world, we're happily ignoring Vista's stupid requirements and imposing far more sensible ones, which can be done pretty easily because it's efficient, reliable and is ignoring all the DRM crap.
Guess what I run?