I'm sure many people have a Windows 7 license they use for VMware/Parallels around here. If I were to do this gaming rig, I'd use the license from that. Useful to state that I don't use my W7 license for anything other than the oddball windows app that I want to run. It isn't a work related necessity. Your use may vary, obviously.

Second, the case they recommend is complete trash. I'd suggest spending a few extra dollars on a quality power supply. The one they recommend has a PSU with the case, and it isn't compatible with north american voltages. So get something better there.

No one is really going to plug a PC into a television to play modern warfare 3 (I'd hope). Not when you can spend less on a console and get the same experience. Granted, my personal preference for shooters is a keyboard and mouse but I'm not huge into these shooters anymore.

That said, I'd just spend the cash on a console and spare myself the cheap parts that they have recommended. Expect to spend at least $500-750 for a reasonable machine that won't start your house on fire, die within a few months, or cause you headaches down the road.

I'd pass.