If you have had multiple virus infections and your computer is still not running properly after removing them I would reload the machine and then promptly install some firewall and antivirus software BEFORE connecting back to the internet. Just because you "remove" a virus it doesn't mean that any damage the virus did has been undone. There could still be damaged files or remnants of the malicious code on your system. A reload is the only way to be sure that you fix what the virus did.