About to built a new rig, let me know what you think.
Don't need to worry about the keyboard, mouse, monitor, sound, speakers, case (TT Armor w/25cm fan), or PSU (OCZ GameXtreme 700w). Will be running games like Company of Heroes, Civ IV, and Oblivion at 12x10 and running progs like IE, MS Office and Photoshop.
Also, planning on overclocking proc to at least 3.2 and overclocking video (probably with ATItool).
Might get into RAID a little later, had a bad experience with my current 0 setup.
The 8800GTS 320mb would work fine for the resolution you play at with max settings. However. If you plan on upgrading your monitor and playing at larger resolutions I would highly recommend getting the 640mb version.
I wouldn't advise getting a 320 regardless of resolution, some games already out require more than 320mb for the highest texture setting, it seems a shame to buy a high end GPU and then cripple it with low memory