I use Avira. You might find this helpful:Simple and easy ways to keep your computer safe and secure on the InternetFree Antivirus Programs
*You should only use one antivirus programAVASTAVGAVIRAFree Antispyware ProgramsSUPERAntispyware Free EditionMalwarebytes Anti-MalwareSpyware Terminator
*Provides Real-time protection. During download, you will first be prompted to download Web Security Guard
Toolbar.This program is similar to McAfee Site Advisor. You can bypass the Web Security Guard by scrolling down to the Free Antispyware protection section.
*During Setup, you will again be prompted to download Web Security Guard. Be sure to uncheck it if you do not want it.Spyware Blaster
*Prevent the installation of ActiveX-based spyware, adware, browser hijackers, dialers, and other potentially unwanted software.
to view the spywareblaster tutorial.Free FireWalls
*You should only use one firewall
to view tutorial on Firewalls.Comodo Firewall
*Comes bundled with Comodo Antivirus->when prompted to not download Antivirus if you already have an Antivirus program.Zone AlarmPC Tools Firewall Plus