CPU Usage problems

Hello, I noticed today that my CPU usage is jumping from 70-100% at times when Im only running one game (World of Warcraft) and ventrillo (Voice Chat). Everything seems so be slower and choppy at some points.

Here is some info about my computer:
CPU - 2.4G Core 2 Duo
Video - NVIDIA GeForce 7900 GT/GTO (512 MB)
2G RAM

I run the game in windowed mode with duel monitor displays. My only guess is this could be the problem but I though this computer could of handled it. If anyone has an suggestions to why it could be happening that would be great.

Thanks,
Brian

 

Bump please.