Which antivirus program should I remove?

I know that having 2 antivirus programs can sometimes be harmful to your computer. I have CA with my current internet provider and I just learned that I also have protection with the Windows Security Center. I have heard of some programs being able to work together and I just want know if one of these should be removed, and if so, which one. Also, if I need to get rid of one, do I remove the entire program or just disable it?

Which antivirus program should I remove?anti virus

Security Center is not an antivirus program. You should not remove this component as it advises the user according to how protected is the computer (firewall, automatic updates, virus protection).

Since you already have CA, there is no need to install another, unless you want to try out some free alternatives.

Which antivirus program should I remove?auto protect

Windows Security Center is not an antivirus or a security program, it is there to monitor the types of antivirus/firewall programs you use to protect your computer.
Keep them both. Use them both. They perform different task.
Windows Security Center is not any kind of protection. All WSC does is monitor your other installed security programs (anti-virus, anti-spy, firewall) and alert you if there is any problems.

Keep your CA!