Got it. I think the i7 and 8+GB ram would be pretty good. The graphics card will just improve your display. It won't speed up processing the video files. Unless you're also going to get into 3D work, etc. you probably don't need all that great of a card, except maybe to push two large DVI monitors or something.

You will probably need an additional, large hard drive. The pieces of video and temp space needed for processing can be large and add up.