Looking at your selection, your making a gaming system.
However, I build computer systems and servers and have been following HD tech and system hardware..
Firstly the board you selected is good.
I would go for a quad core processor, most of the software are gearing towards this. for comparison. my AMD 4600 V Q6600 encodes video 7 times faster. ( my guess from memory, its around 10 times faster than a single core)
For Memory(RAM) I would look at 2 or 4 gigabytes of faster DDR than the FSB.
For storage (hard drives) you should be looking at SATA2 Hard drives, the price has dropped and a 500 gig hard drive is cheap.
Make sure you get a good power supply to go with it all 650 watts ATX2 should fit your needs.
Personally I went for the ATI 1950 Pro VIVO card, for obvious reasons, rendering and input.
Vision wise I went for two Samsung SW206BW monitors - but they just do HD specs but are very good in there specs. (1680x1050)
Optical storage would have to be blue ray, 24 Gig discs will help you keep all that video.
On a side note the spec's I just said are vista and HDCP compliant systems.
Need Pro Computer advice?