There is no one size fits all when it comes to computer security. What works well for me may not work well for you. You just need to find a program that plays nice with your computer. FWIW, several years ago I tried a trial version of Panda Internet Security. It made my computer crawl slower than a turtle. Stayed on for 10 minutes before I uninstalled it.
I agree with Boopme, get rid of it and get your money back. Try one of the free programs in Boopme's link.
And if you really want to purchase a program, see if that program has a trial offer. You'll find out real quick if it works with your system.
PS-the McAfee product you mention includes antivirus, so don't forget to install another one.
Edited by Queen-Evie, 21 August 2008 - 09:44 PM.