Scan your PC with an Bootable ISO or USB from AVG

AVG rescue CD from Grisoft.

Czech company AVG is well known for their antivirus/antispyware solutions. Besides the Free Antivirus solution they provide as an installable version – The AVG 9 Free, there is another tool. It's an ISO image you can burn to a CD and scan and clean your computer before your Operating system starts. It's an AVG Rescue CD.

This process is sometimes necessary, since an installed version of your antivirus software can be already compromised. What to you need to do is boot from this bootable media and scan and clean your PC from viruses.

The AVG Rescue CD comes in two products:

• an ISO image that can be easily burned to CD
• Compressed version that can be installed to a bootable flash drive.

Check this: antivirus/antispyware solutions 

Once done, you can simply boot from the drive of choice directly to the AVG menu. In that menu you can scan for viruses, edit files, test your drive, or even edit the registry. The bootable CD is based on a version of Linux, you can also access a number of common Linux tools.

Download Rescue CD (for CD creation)

Download Rescue CD (for USB stick)

What's the Features of the The AVG Rescue CD?

–  Comprehensive administration toolkit
–  System recovery from virus and spyware infections
–  Suitable for recovering MS Windows and Linux operating systems (FAT32 and NTFS file systems)
–  Ability to perform a clean boot from CD or USB stick
–  Free support and service for paid license holders of any AVG product
–  FAQ and Free Forum self-help support for AVG Free users

Source: LifeHacker