You're welcome artkaye..
I use 'avast' as my full time a/v program that runs in the background. I also use 'a-squared' to double check.....and when I scan with a-squared I stop 'avast' from running in the background. Running two a/v's at the same time can cause problems....so run one at a time. I update them daily and also scan with them daily. There are links in my sig for both, and they have free versions.
Also a firewall is a must..You don't want to be on line without a firewall, so use XP's firewall to go on line to download the programs you want/need.
I like Zone Alarm free, but there are some other good free firewalls available, as you will read here in the forums....
it is not recommended running two firewalls at the same time. XP's firewall only stops incoming, whereas Zone Alarm and others stop traffic in and out..which is important in case you are unknowingly infected with malware that wants to 'phone home', so to speak.
btw my signature contains all the programs I use for protection/security, you might check some of them out.....any further questions or assistance , post back your questions.
hth