With overlapping RESIDENT protection you find that (as an example) Spybot's Teatimer notes a change, so does something else and then the other notices the other looking and the result is a slow machine.
I'd toss out Spybot for now.
I am running Win XP Pro, 80GHD, 1G ram. I have a variety of security programs running and I'm concerned that some may be redundant.
I am running AVG, (free version), Zone alarm, (free version), Microsoft security essentials, (free version), Registry Mechanic, (paid version).
I also run adaware, (free version), Spy-bot, search and destroy, (free version), windows defender. Any input will be greatly appreciated.