[MomwithHope]

I run XP SP3 on 2 computers with Norton and have had no problems ever. Norton has caught a few attacks over the years.

[Slump Tester]

I used to use Norton Utilities and NAV, and loved it. Now I use Microsoft Security Essentials. It's 100% free, there's no subscription to expire, and it integrates easily into your environment.

I'd get Security Essentials for your XP boxes while it's still being offered. (I believe the daily virus definitions are the same for all the OS's, but I may be wrong.)

[rarestia]

Norton has caught a few attacks over the years.

The majority of online identity thefts and PC security breaches occur from malware and adware nowadays. Virus detection suites are becoming passé. You could have a full complement of protective measures in place, and one errant click in an email could send every last piece of personal data across the wire or could install a program to track you keystrokes.

Everyone needs to understand that viruses are not the only vectors for PC violations. Having an OS with a bad kernel, which is essentially what you have with XP, leaves you susceptible to kernel-mode and driver attacks that no virus scanning program will detect.