That's a legitimate question, and one that I had had myself at first when I used Win2k/XP but now I don't have to worry about System Idle Process using up the Idle CPU cycles. I use FaD to use those idle CPU cycles to crunch for a cure for cancer, SARS, HIV/AIDS, as well as many other projects...
Find more info
HERE...
And the best thing is that it has NO effect on your tasks that you do on the computer, whether you're gaming, video editing, photoshopping, browsing the 'net, checking email, anything. So it's a great cause and it really costs you nothing!
Think about it...
Also, have you gone to windows update and got the latest patches for IE? Especially any Service Packs...
David