Antivirus 7 (virus ???)

Hi to everyone, found this site on mums netbook after mine got infected by this pop up every couple minutes stating antivirus 7 you have loads of infections. I have AVG 9.0 free, Adware, nothing was stopped by these I now have Spybot and Microsoft essentials, it totally blocked my browser and everything I tried to do was blocked I am using XP, Mum searched your site and managed to restore to previous uninfected day as it happened yesterday when I went to yahoo mail. What is this thing and it's pseudonyms
It seems to be free of this now and working fine. But is this still hiding somewhere how do i tell and what should I do next am not that good at techie stuff.
Many thanks in advance
Luke

Hello.

I will have a fix for you as soon as possible.

My tool can detect that.

Please download Cheetah-Anti-Rogue, and save to your Desktop.

• Double-click on Cheetah-Anti-Rogue.zip, and extract the file to your Desktop.
  
• Double-click on Cheetah-Anti-Rogue.cmd to start.
  
• It will finish quickly and launch a log.
  
• Post the contents of it in your next reply.