sp2 messed up my comp too. after i installed it, i restarted and lo and behold i have about 10 random icons on my desktop (aka spyware/viruses). i also got an increased number of pop-ups.
i had loads of problems with it the only way i could get it too work with sp2 was too do a clean install of windows then install sp2 then all my programs otherwise it just screwed it up
apparently you cant have any UMAX scanner drivers on your computer when you install SP2. This is the perfect description of what happens to me, but I am pretty sure that I have no UMAX scanner drivers on here. I searched my C drive and found a few files with umax in the title but they appear to be support files for autocad and 3d viz.