Ten years online, same old generic PC, Windows, Explorer, etc. Never had one single problem relating to viruses. Had a trojan once.

Worst problems? MacAfee AV, crashed my computer, wouldn't let it boot up, and was so entwined in the registry, etc., it took a techie three hours to clean it out. Twice. Because the next (hired for something else) tech thought it couldn't have been MacAfee's fault and installed it again from his clean-for-customers disc.