There are thousands and millions of different programs that are out there in the virus/spyware removal category. Also most of these programs are free which a good thing is. Different programs will give you different results and thus it depends on what exactly you wish to get from these programs. Hence the best thing that you can do when your computer is infected with multiple viruses is to run multiple programs. In order to get around this thing, you can either scan the system or you can enter the safe mode on your Windows system.
In addition to entering the safe mode, you can also scan your computer before your Windows has a chance of getting booted up. This can be done by utilizing an offline virus scanner and sometimes a pre- boot scanner. The way that this works is that you will have to use another computer to properly download a file for ISO image from any anti- virus company.
A clean install is not meant to be the most fun thing to do. However, it is a method that can guarantee you to get rid of all the viruses, malware as well as spyware. It is also pretty straight forward, when you are able to do a clean install. You will be able to delete everything on your hard disk and therefore there will not be any viruses. There will also be times, when a virus will not be able to infect items like text documents, pictures, MP3 files and videos. Here, a good thing to do is to scan all your personal data and even then if there are no viruses to be found, you can copy it to your external drive.