Windows XP NTLDR is missing

So I am fixing this person's computer that had over 1,000 viruses, trojan horses and malware. I got what to believe most of them off of the computer using free spybot. They didn't have any real virus protection program on their computer and didn't want to pay for any. Well I had the computer working about as good as it could with only 512mb's of ram, but here is where the problem occurred. I had the person come get their computer this morning, went to turn it on to show them how fast it was compaired to when they brought it too me and I got the "NTLDR is missing" prompt and it will only let me reboot. So I put a valid version of Windows XP in to do a repair and I get to the command prompt, but I am unsure what to do now. Is their a way to pull the files i need off of the disk or am i going to lose everything on the hd and have to reformat? Is it possible to put a second version of xp on the same partition without losing the info and then finding the files i need and putting them in the original version or keeping the second one and deleting the first one? Any help on this would be greatly appreciated.

BirdM4n33

 

Now is it missing <system root>\system32\hal.dll

Thanks for the info before Pete, it worked, i can get back into windows, but i still really don't want to reformat if i don't want to. Now it is telling me if i boot up without that disc in that system root\system32\hal.dll is missing. Know where i can get that file from and where to put it? Thanks