Howtogeek posted a tutorial about using the Avira Rescue CD to clean your infected PC

When you've got a PC completely infected with viruses, sometimes it's best to reboot into a rescue disc and run a full virus scan from there. Here's how to use the Avira Rescue CD to clean an infected PC.
We've previously covered how to clean an infected PC using the BitDefender or Kaspersky rescue disks, and loads of readers have written in saying thanks, and reporting that they were able to clean their PC easily.

  How to Use the Avira Rescue CD to Clean Your Infected PC