Ok the different SP2 paths..

XP original - SP1 - SP2
XP original - Patches - SP1 - SP2
XP original - Patches - SP1 - Patches - SP2
XP original - SP1 - Patches - SP2
XP original - SP2
XP SP1 - SP2
XP SP1 - Patches - SP2
Also what else is thrown into the fray.. DotNET?, DirextX, Java VM, Sun Java.. (was DirectX upgraded or Dotnet upgraded during the SP2 install? or some other application)

MAny OEM installs have Sun JAva included while your OWn install path may not or worse MS Java VM...
YEs MS VM is not removed on the SP2 Install (assuming it was there in the first place)..
Could there be a funny Java issue here? (had a funny issue with a local car dealership involving a problem with MS VM and Sun JAva in a machine..

I assume No AV involved at anytime here

Only thoughts.. sorry I cant help more..