Windows XP registry missing "active controlset key"?

[Paradax]

Alright so I'm working on a friends laptop he had a virus (it was on of those "you have a virus download antivirus 2010 to fix it" ones) I don't know any more about the actual virus than that but now it won't boot into windows. When you turn it on it says that c:\windows\system32\config\SYSTEM is missing or corrupt and that you might be able to repair it with a windows installation disc and the repair console. So I booted with a slax livecd and ran clamav and avast antivirus both of them found viruses in his limewire downloads(big suprise) so I deleted the files it said were infected then booted from a windows xp disc. I then went into the repair console and after I login, or run the login or enable commands it says "the system registry does not appear to have an active controlset key. The system registry may be damaged. If your system is not starting correctly you can try restarting using the last known good configuration or try repairing using the repair console.".

 

Could someone whohas more technical knowledge than I explain what the controlset key is? Is this repairable or does he just need a clean windows install? Is there any way to boot with the last known good configuration cause as soon as it gets past the toshiba screen it says system 32 is screwed up and it doesn't let me do anything after that? Any help would be greatly appreciated.

[MasterRex862]

Why not try a repair installation of Windows? If it's successful, your friend won't lose any data.

 

If necessary, click here for a quick how-to.