How do I remove a computer virus with out buying or downloading anything?

An antivirus program downloaded it's self and I was told that it is a virus but I don't have the money to buy a software or an Internet connection right now so is there a way that I can remove it. I have a toshiba laptop with windows 7
The viruses name is Antimalware Doctor

you can try System Restore, but I am not sure if it will work or not. You really need an internet connection so you can download an antivirus cleaner, like Microsoft Safety Scanner. It is a one-time download, and it requires no install. Definitions are built-in, so you can download somewhere else hopefully, then copy to the computer and just click scan. It scans for any viruses and malware, then it removes it.

You know, You could down load AVAST ANTI VIRUS(Free Version) without compromising anything.
Your Toshiba laptop must have some kind of antivirus otherwise you will lose your laptop to viruses.

Now, you want to get ride off the one that you thought was anti virus......Ok
Go to start button type "system configuration"a small table shows up click continue....system configuration shows up, click on service and look for that virus or anti virus protection that downloaded itself.....disable it......then click on start up and do the same thing........You have disabled it completely.
If you decided to download AVAST, have no fear you will be fine with free version.....

It would be helpful to know the name of the Fake AV product downloaded on the computer ?