What do you want?
Do you want and need a Windows operating system for some reason? You can probably clean Vista of most of its infections and reinstall it from its restore partition and have it work. You can start by downloading the free.version of AVG antivirus to replace the program that is not active.
Have you googled the model number of you Vaio with linux to see if this machine is well suited for linux or has devices that present problems? You can also do a test by downloading and burning one or more live-cds and booting them to test the system for function. Here is the standard list.
Burn the download as an ISO image file at a low speed on a good quality cd, and use the key for a one-time boot that you will see when the systems does its POST to boot from the CD drive.
If you are to keep Vista, you may also install linux along with it as a dual boot. If you format all of the HDD for linux, you will have eliminated all threats of a virus. You have a number of choices open to you. Good Luck