I have been working on a friends pc it is a compaq presario w/ AMD Athalon, 512 G RAM, XP Home SP3. The pc was having an issue with pop-ups, and when I tried to begin working on it alot of .exe's were corrupted.I noticed the version of avg on the pc was expired. I deleted a few known malware programs such as PC Power Speed etc. and I was able to execute the programs that said they had a corrupted .exe. As I dug further I noticed windows firewall and automatic updates were disabled and could not be activated. I then went into Safe Mode with Com Prompt and got them turned on. Ran numerous scans with AVG, Malware bytes and Super Anti Spyware. I removed 7 Trojans, Many Tracking cookies and repaired 3 Reg errors. The pc is running much better than it was and i now have access to everything but it is still running slower than it should and when you have any program open, even if its is just sitting there idling, it is extrememly slow when doing other things, slower than it was before the infections that have been resloved. I would like the get this pc back to the owner soon and was wondering if anyone had any ideas i haven't thought of besides a reformat and reinstall of the os and everything else. Thank you for time and help.