yeah, IE works fine for me. why, what does everyone else use these days?
IE is slow and inefficient, riddled with security holes (though admittedly it's much better than it used to be, it's still far from acceptable), and completely fails to comply with a large number of web standards which, as Havok said, means it's a real bitch getting websites to work on it properly. It's generally a terrible browser.
Personally I use Firefox, which is great. Many people use Chrome, which is also a good browser (though it had a couple of annoying niggles which put me off). Some use Opera, which I've never tried, but has a generally good reputation.