Can't really say I can relate to mgookin.
But Salmon, on the other hand, I relate to almost completely. I have actually had more problems with systems that weren't updated than were.
If you were never, ever going to connect a computer to the internet, and never ever introduce any kind of media to it (through USB, CDs or DVDs, etc.), then you wouldn't need antivirus. However, your only safe "take it with you" output option would be a printer.