Laptop Re-boots Before Completing Automatic Update

I have a laptop (Compaq Presario R3000) running XP Pro SP2 with Office 2003
installed. Lately I have been having trouble with automatic updates. It
reboots before completing the installation and runs real slow when I can get
it up at all. The updates currently in question are Office 2003 SP3 and
KB923414.

I also had trouble with the last automatic update which took a real long
time to complete because of similar behavior.

Any help with getting through this would be appreciated. I'd hate to have
to scrub the machine and reinstall everything to fix this and to be able to
use the machine.

Thanks,
Eagle