Do any of you know how to get rid of the 'Windows 2010 Security' virus?

I was quite shocked today to find a ‘Windows security’ window pop up claiming that my computer is full of viruses. However, when I googled it up and it seems that the security window itself is actually a virus. I now can’t open any of the files on my desktop and every time I do get something to work, the ‘Windows security’ will open up again. No matter how many times I end ‘av.exe’ with task manager or try to delete files it always comes back. I’ve seen viruses before but most of them were pretty easy to solve.
Help, anyone?