The good news, Melo, is that it's probably not doing any more damage other than popping up in your face way too often.
An alternative to getting a virus/malware scrubber tool, which you may want to do anyway, is to use a backup/restore tool. For example, on something like Windows XP, etc., you can use the System Restore tool to run your system like it was before yesterday and that should rid you of the problem in a lot of cases. The trouble is if you installed something useful since then.