Here is a build I put together today. I am looking to buy the parts very soon so any an all criticism is appreciated.
I have not followed hardware closely so I am sure I have made some errors. Also I am currently clueless on which video card to pick. This system will be for my general use and gaming as well. I hope to future proof as much as is reasonably possible.
I would also appreciate recommendations on which 64-bit Vista to get. My concerns there are gaming and minimizing the dreadful Microsoft DRM and other BS.
Good layout so far. For OS I would get recommend Home Premium 64. I use it and have had barely any problems with it.
As for the video card, you say one of the uses is gaming. You haven't said a lot about your budget but seeing as you have an Intel chipset based board you have 2 choices. Either go with 2 ATI cards in crossfire eg 2 x 3870 or 3850 or go with one nvidia card in the 8800 series preferably a single GTX as you can't do SLI. As I say it pretty much depends on your budget and the types of games you'll be playing.
I see you are also torn between and core 2 duo and a quad core. This really depends on what you mean by general use and what programs you will be using. Not many games take advantage of quad core CPUs at the moment and not a lot of programs do either. You will only benefit from a quad core if you are doing things like photoshop or using 3D design softare.
Saying this, if the 2 are the same price, then you may as well go with the Q6600 and have the 2 extra cores for the future. Just be aware that there are new CPU's (both core 2 duo and quad core) coming out within the next few weeks. I know you say you want to build soon but the new 45nm chips would be worth the wait if you could.
I would recommend to try and go with 2 x 2gb ram instead of 4 x 1gb (obviously if you can afford too) as it helps in numerous ways eg less stress on the memory controller, less heat, less chance of a module being faulty, better overclockability etc. Anyway ballistix is good stuff.
Another thing is you say that you will add a second hard drive later on to form a raid array. You may know this but some raid arrays require both hard drives to be formatted and so if you add the second HD later you may have to completely wipe the first.
hope this helps a bit. any more question just ask.