Help how do I get rid of virus trojan horse downloader.swizzor.jvp

[june]

I have a free zonealarm firewall and avg running
After downloading the latest free version AVG 8.5 I decided to run a full scan of my system overnight to my dismay in the morning AVG reported
Threat detected!
C:\System Volume Information\_restore{28D91BCD-B656-4C8D-----.exe
Threat Name Trojan horse downloader.swizzor.jvp
I have tried to remove this an it keeps popping up again.
Itried to report it to AVG but cannot find the link on AVG.
Before reformatting XP on my hard disk can anyone help ?

[june]

Thanks Tony of systems-edge.co.uk  your instructions were first class the virus has gone for good the systems running a lot faster.
Tony said go into ALL PROGRAMS, ACCESSORIES, SYSTEM TOOLS, SYSTEM RESTORE, SYSTEM RESTORE SETTINGS, tick the box TURN OFF SYSTEM RESTORE, click on ok.
Its a good idea to get rid of all those unwanted cookies spybot-s&d is known to be very good and can be downloaded from
http://www.safer-networking.org/en/home/index.html
after removing the cookies reboot the computer and turn  system restore back ON and label something appropriate.
Now run the latest free version of AVG (8.5 or above)
everything should be ok.
Take a look at http://www.wiki-security.com/wiki/Parasite/Swizzor
to learn more about this problem.
Finaly if all is ok I would setup another restore point.