Unfortunately, different anti-virus companies have different naming conventions for viruses, so it’s possible that one virus will have many names depending on the site you visit.
I’d say go with the site that has details about the kjwall.gif file you found on your system. Hopefully it can tell you how to safely remove it (without formatting your system anyway).
The security forum at Broadband Reports may also be able to give you some advice:
http://www.broadbandreports.com/forum/security,1