My 1st post!!!

I want to build a new computer. I have been doing more and more video editing, and my 5 year old PC just isnt cutting it. I know the basics, but am not that familiar with the hardware demands of video editing. I am a little lost on the video card. I'd appreciate it if someone can answer this question. Is the video card a critical component in video editing? Does it actually do any work while editing video or is it all done by the CPU?

What kind of card should I be looking at? I want it to be able to support 2 lcd monitors.