System Usage from Most to Least Important: Archiving DVD and Blu-Ray and CD collection, Home Video editing (some HD) Surfing the net, some picture editing and some gaming. Games like Diablo III, WOW.
I'm not a WOW player but Blizzard games aren't as resource - intensive as a game like Skyrim is.
Parts Not Required: Keyboard and Mouse. (open to suggestions if someone feels this is really important)
I'm really in the minority around here on this one but I really feel that the keyboard / mouse is the least important part of a system. I'll never spend hundreds on peripherals and aside from an XBOX controller and a wireless keyboard/mouse that's really all you need anymore.
Monitor Resolution: brand and resolution suggestions welcome.
I'd suggest making the monitor a separate purchase from your build. The thing is with HD prices at really ridiculous levels due to the Thailand situation it can be really difficult to get a build under $1K with monitor and OS. But you definitely want at least a 22 - 24" monitor with 1080p resolution. Asus and Acer are usually my top choices for monitors but Viewsonic, Dell, and Hannspree are also pretty popular choices as well.
Maybe try this build. It doesn't include monitor but it should give you an idea: