Be extremely careful if modifying the 'userinit' registry variable, BTW. If
you get it wrong you'll end-up with the computer continually logging you on
then off again in an endless loop, and this is very difficult to resolve.
Which does bring-in the point that spyware can cause these kinds of
symptoms. Try a scan with ad-awware.
BTW, the MyLogon link is just my sig, it's not intended for standalone or
home computers.