Windows XP Home startup error.. please help

Thank you in advance for taking the time to read my problem... When I go to boot up my computer I get an error before it even loads Windows saying," Windows could not start because the following file is missing \Windows\SYSTEM32\CONFISYSTEM" now the only CD I have is the Reinstalltion CD that came with my moms laptop... So when I try to boot with that CD I get to the DOS Windows Repair/Recoverey, but I have no idea what I need to do.. Like what text I need to type in to repair that. Can somebody please help me out and tell me what I need to do to fix this problem? I have 2 harddrives that are on that computer C: and D:
Thanks,
Omen

 

I meant CONFIG\SYSTEM.. sorry for the confusion if any