My suggestion would depend on the video editing you do. The i7 920 has hyperthreading to support higher multitasking ability. The 920 is no slouch in games either. It's right there at the top in most benchmarks. You could OC the 920 and get even better performance.
If you don't want to OC, I would suggest the i7 860, which also has hyperthreading, and a faster bus. It's an 1156 socket though, as opposed to the 1366 of the i7 920.
If you aren't doing intense video rendering, I would suggest the i5 750.
If you're only going to run a single video card, I'd suggest this 550w OCZ
http://www.newegg.com/Product/Prod [...] 6817341022
Since your getting windows 7, you may want to look at the 5770 to take advantage of dx11. If you're into heavy gaming, the 5850 is nice if you can find one.