Should I get rid of Norton Antivirus 2002?

I have two computers, one being my primary and the other being its seldom used predecessor. While most of my day-to-day work is performed on my newer Mac os x, I do occasionally use the older desktop computer (with Windows XP) to check email, type doents, and burn CDs. The problem is that it is outrageously slow. I'm in the process of trying to clean things up, and I am wondering if it wouldn't be unwise to remove the old Norton Antivirus 2002 to help alleviate the lag. Any suggestions?