|It sounds like you hal.dll is corrupted and windows is not running a multiprocessor hardware abstraction layer.|
Go to your device manager, expand computer.
Does it say uniprocessor or multiprocessor?
Anyway here's the Microsoft write up on the Hal.dll
You are going to want to backup your stuff, just in case, changing the hal can lead to problems, but if the system was originally installed as a multiprocessor system, then you should be safe.
Let me know if this is your problem.