Even if that's all you've ever had go wrong when editing the registry, that doesn't mean worse things couldn't happen. Please, just do yourself and us a favor and take it to a shop, have them fix it, and then install an antivirus.
i agree, also try doing what i said up there, it works for me.
ohh and get norton, like i said before, it helps alot......and dont whine and say "im not downloading AV software!" because were just going to tell you to over and over and over until you do.