Infected with something - unable to logon to a user

Just got infected - XPSvcpk2

 

Had a bunch of Norton "warning; infected" messages - immediately ran liveupdate.

 

Think some alleged spyware pgm "MS Antispy" was loaded and started to run (cancelled it)

 

went to safe mode, scanned, no infections.

 

restarted - no matter which user I launch same thing happens:  starts to load user prefs, then immediately logs off and saves user prefs.

 

now cannot even get into safe mode.

 

WHAT TO DO?