4 viruses and can't boot windows

My brother has windows xp home sp2 and suspects from a website using firefox he got infected. Mcafee was giving him warnings that he didn't get a chance to read before his pc froze and he shut it off. Now he can't boot even safe mode getting blue screen Stop 0x0000007B or STOP 0x00000024. I did chkdsk and tried dells diagnostics but nothing. Tried fixmbr and fixboot. I booted from a linux cd and scanned for viruses with avira. 4 viruses found as .tmp files in documents and settings/username/local settings/temp in files created right about when it froze. when I ran avira again to delete instead of just scan it deleted 2 of them (FakAV.XN.4 and TR.Crypt.PEPM.Gen) couldn't delete 1 (TR/Vilsel.mcr) and didn't see another (TR/Alureon.CT.100) the 2nd time. Rescan it's finding nothing but I still can't boot or find the files it previously detected but didn't delete. What can I try now? Windows repair installation? I don't want to format and lose the data.