You run into the crossroads with what you want. You can do some low level gaming with that, a 24" monitor (LCD so you have response time) would be hard for a 6800GS to pull off, am I correct?
The system Havok built is very nice, if gaming is a secondary, which from what I gather, it is, you should be fine. You'll be very happy with that computer if you decide to build it.
And I suggest that you build it yourself, or go to a local computer repair technician and ask him to assemble it in your stead. When you custom build you can assure quality parts (like those Havok detailed) and you aquire volumes of knowledge.
I would also like the mention that it would be good to have 2GB RAM, its not need for routine Windows operation now, not by a long shot, but when Vista comes around, it will help. Not to mention that it will help when you are multi-tasking.
And at last, thank you very
much for making such a wonderfully coherent post. It is neatly space and orgranized with the summary stating "in a nutshell" what you are looking for. I've been on this forum a relativly short time 3-4 months but I've seen to many, "WHICH RAM SHOULD I GET [UNNAMED LINK] OR [UNNAMED LINK 2]" If happy to answer, but at least word it correctly!
Alright, sorry for the rant. But thanks for putting up with it!