BAD POOL CALLER ERROR?

when i boot up windows xp i get a bad pool caller error on a blue screen. in order to get windows past the loading screen into the user select screen i have to unplug my USB mouse and printer. i have tried updating drivers (which all say there working fine) with divermagic pro and through device manager, but to no avail. please please help this has been bugging me for months!

danny boy