Unless IE crashes on a particular website (there could be some sort of script running which screws it up), then I would agree with Sam, and speculate a deeper problem with IE or your Windows installation. Try Firefox and see if that improves things, and of course, you must be one of a small minority still on dial up, so I would suggest shopping round for a broadband provider, which should definitely improve your connection speeds. If things don't improve, come back to us with some details of your machine, particularly which version of Windows you are using. If you are using a version prior to XP, you may be able to re-install Internet Explorer, which could possibly rectify things.
By the way, how much stuff did Ad Aware and Spybot find? I assume you did allow it to delete all the rubbish?