Big problem with a virus

[GoldSpot]

I caught a virus while downloading a film on a forum , since my pc start lagging " lag of death."
In the bottom of the main screen, I have a message saying that a virus, and no way to removal that .
I run several times avast, do the scans start to check my system, there were 3-4 virus found, but after that my pc hangs (I've done it 3-4 times). So no way to get rid of this virus
Please help me

[need Tos]

download HJTInstall.exe ( do some google search )

Saves HJTInstall.exe on your office
--) Double-click on HJTInstall.exe to launch the program
--) By default, it will install here C: \ Program Files \ Trend Micro \ HijackThis
--) Accepts the license by clicking "I Accept"
--) Choose the option "Do a system scan and save a log file"
--) Click "Save log" to save the report, which will open with notepad
--) Click on "Edit -> Select All", then "Edition -> Copy to copy the entire contents of the report
--) report that you just copy it to this forum