There are many things this could be... HAL stands for Hardware Abstraction Layer, and is basically what MS_DOS was for Windows 3.1 and Windows 95,98, it's what allows Windows to talk to your hardware.
Do a google search on hal.dll, you should get many results as to what the problem may be...
try:
http://www.computerhope.com/issues/ch000490.htm
Hope this helps,
Flip