My HP computer came with McAfee and it never worked right. Even trying a clean install of a retail disk didn't work. Then I went to Norton. :'(
Norton -- what can I say.
Having helped friends with crashing computers and all sorts of application failures due to a conflict with NAV's auto protect and the new version -- 2004 -- garbage. Literally invades the registry and nearly everything on the computer -- slows down operations, snags start-ups and if you've installed Windows Updates -- forget it. It's a mess and as Technical will tell you, it's even worse trying to uninstall it. I found the best way is to just wipe the hard drive, reformat and reinstall XP.
Avast --
-- THE BEST! Easy to work with, does the job neatly. And, don't forget, we've got the greatest forum to help us when we have problems or questions. The Avast Team will not let you down!
Dave