Make sure you have the latest Windows security updates in place, as one of them may patch the vulnerability. I wouldn't be satisfied with leaving it on there and using another browser (although FireFox is the long term answer). Do you have a firewall running? Try a software firewall like Sygate or ZoneAlarm. They may alert you to any outbound traffic that could be causing this, which would allow you get rid of the source. Sounds like you may have other major problems given the results of your other scans. What OS are you running? Windows 2000? XP? Might be a good time for a rebuild given what else is going on.