What does the error report say (ie which program/app crashed)?
As a first resort try running scandisk to see if you have any corrupt
files or drivers.
Assuming you run gpl in D3D, try running dxdiag (it's in your WINNT folder
or just go start, run, dxdiag) to see if there is a problem with directx.
Do you have any other games you can reproduce the error with?
Malc.