I think I've only ever had 3 viruses. The first one was the "kak" virus after only owning a pc for 1 week, and I only knew I had it when the virus somehow got deleted and I got an error on bootup saying it couldn't find the file!
The other 2 were the antinny.G virus, both on the same day, from a zip file downloaded off winny. The really stupid thing wad I knew there was a virus but the damn thing tricked me into clicking the file anyway! ... The zip was supposed to contain mp3's but the filenames were so long it wouldnt extract, all except the virus which would extract, but I was careful not to click on it... yet! So, I want to extract the mp3's because even though there's a virus in there the mp3's might be legit, so in the end I find a way to extract the files and there's a load of folders all inside each other, so I'm clicking to go inside the folder, and there's another folder, so i click again, and there's another one, and whopps it's an exe that has a folder icon. Then after disinfecting my pc I stupidly did it again and had to disinfect it again.
After all that they weren't mp3's but something to do with linux.
Oh, and I got a dialler off Robbs Celebs, that bloody site is infested with them, or was, I've not been there for years. Strangely enough on the same day I also got a dialler off an email that downloaded and installed automatically when I just viewed the email in the preview pane (presumably through some javascript). They were easy enough to remove myself, I didn't even have to google anything.
As for Genuine Advantage, if you have your pc set to do the monthly automatic updates, don't have it set to download automatically, set it so it asks you first before downloading. Then each month it'll give you a list of updates and you can read the description for each one carefully and choose not to download the ones you don't want.