I've got a virus - help!?

I have no idea how to get rid of it. Norton anti-virus isn't detecting it. I used Windows' ''Remove malicious hardware'', it scanned my entire computer (took 5 hours) and came up with nothing. I've tried installing Avast but it keeps closing it down before I can even get anywhere with it. So far I've cleaned off about three of four folders that were obviously downloaded with the virus. This stupid virus won't allow me to open up the help section on my computer and it's slowing everything down considerably. There's warnings in my system tray that aren't authentic Window warnings as they lead to anti virus sites with ridiculous pop ups and the grammar is horrible ex. ''You computer is infected!!''

I've tried system restore and that didn't help either %26gt;%26lt; Agh I'm at my wits end.

I've got a virus - help!?free spyware remover

Virus Detection and Removal:

Most antivirus programs can not scan, repair or remove file that are in use. So a normal scan of your computer while the operating system is running can miss many virus files.

Therefore it is necessary to scan your computer with a virus scanning tool that is able to do a boot scan. This basically means that it scans the HDD(s) for viruses before loading the operating system.

Another common problem seen is the use of several virus scanning programs at the same time. Find one program and use it and remove any others (that does not include ad-ware or spy-ware programs). Keep it updated; however most programs do this automatically if you have internet connection.