My point is that the most intensive thing you're going to be using this system for is Aces High. Everything else you plan on using this for can literally be done on the cheapest processor available right now, and 2GB is more than enough system Ram for this same reason.
With that being said, it all comes down to how much money you want to spend. If you want to be cheap, cheap, cheap... you can definitely find a system that is more than capable for Aces High for $400-500 ($300-400 if you build it yourself). Now, if you want performance, of course you're going to pay for it... If you want something that you can turn on EVERYTHING then obviously it's going to cost more.
Gyrene, making blanket statements like "You're not going to like that video card" is hardly beneficial and downright confusing. I had its virtually identical brother, the 9800GTX+, and NEVER had any problems with it.. including with Aces High updates. Reinstalling Aces High should have nothing to do with the dependability of the video card and its drivers are FAR from flaky. Perhaps you had a defective card.. or perhaps another hardware issue going on.. or maybe Nvidia drivers don't work correctly with your WinEnterprise version... who knows? There are plenty of people playing Aces High with that exact card not experiencing those kinds of problems.
I personally believe that the system I posted is more than enough for everything you plan on using it for... and maybe just a tad better than barely enough to run Aces High at full boat (with shadows off). Yes for another $200 more you can get a much better system, but if you want a pre-built system on the cheap (especially one that comes with an operating system) that is capable of running Aces High reasonably well, what I posted is going to pretty much be the norm.