I have Spybot S&D on my old NT computer, it did help me once but the warnings of it's usage by uninformed non geeks kinda spooked me. but either way I suppose I should get it again for diagnostics. I remember people would ask for it's scanning results while helping one out with problems.
ZoneAlarm, AdAware Spybot S&D kept my old NT workstation going fine for 10 years.
