System 32\hal.dll Missing Need Help!

Ok heres the problem im working on my wifes step dad's computer and his computer crashed because his hal.dll is missing or corrupt.. I tried to run the Repair through the windows xp disc it wont work cause that files missing. But i can access the cd rom and the xp disc through Dos what is the command that i could use to copy that file from The windows disc back to the hard drive. Any info would be greatly appredciated on what i can do...

Look here:
http://www.microsoft.com/resources/documentation/Windows/XP/all/reskit/en-us/Default.asp?url=/resources/documentation/Windows/XP/all/reskit/en-us/prgg_det_pvfh.asp