There may have been other things in the path such as if you have a specific Nvidia card, such as:
C:\Program Files (x86)\NVIDIA Corporation\PhysX\Common;
This is on an x64 system with a GTX 480 in addition to the posted path, but I suppose my point might be you may want to restore back before the error. Davehc might be completely correct, but if you start to see strange behavior as far as program activity, you might consider the restore.
If you haven't had any successful boots since the accident, you may be able replace the Registry using the "Last Known Good Configuration" by hitting the F8 key during boot and selecting it. This option goes away after a successful boot with the current registry settings.