Short answer- NO!

In fact when you run two Anti-Virus programs it is very likely that one or more of the following will happen:
1. Programs crash.
2. You will get plenty of false alarms - what that means is that you will get threats reported while there are none.
3. Your system performance will be crippled.
4. Your computer might "lock up" after reboot. The Antivirus applications start as soon as Windows boots which might cause your computer to lock up.

What to do when you have two Antivirus programs running and your computer locks up right after reboot?

Take the following steps:
Reboot your computer in safe mode.

Unfortunately in safe mode you can not use the Windows Add or remove programs feature. You can use msconfig though. Press the Start button -> Run, type msconfing and press Enter, open the Startup tab and remove the Antivirus programs from your start menu.

Reboot your computer normally, now you can look for ways to uninstall one of them. If you run Windows XP click the Start button then Control Panel -> Add or remove programs, find the Antivirus software you want to uninstall and remove it. In case you still experience problems after the uninstall, due to traces left in the registry, you can try using System Restore to restore your system to a previous stable state.