My sister and my Dad have been getting that AntiVirus popup when surfing Facebook.
I use Opera so its not triggered for me.
BUT
A little education goes a long way. DO NOT CLICK POPUPS. That antivirus popup if you do not click it is fine. alt+F4 to force close a window.
I love imaging... my XP machines usually get full reinstalls every 3-6 months. (Have not had to do a V64 reinstall yet despite 3 motherboard and 4 CPU changes
)
So far I only image my benching rigs... but next ground up build will have a recovery disk done right away