Windows 2000 sr2 shut down lockup

Since installing SR2 for Win 2K I get a shut down lockup where everything closes – saves current settings but the system does not shut down. I am left with a total lockup (ctl-alt del – mouse curser does not work) I have tried to end all tasks including vscan & firewalls before shut down but nothing seems to work. I have to reset then shut down during dos boot.
Any Ideas??