Hmm looks like a pretty good comp, but being honest I wouldn't buy another computer if I were you unless you go for a DX10 card. Cause DME, yes Vista has DX10, but unless your graphics card is capable of running it, it would have no effect and as far as I know, no ATi cards have the ability to do so as of yet. The only card I know of that can is the Nvidia 8800 series. Buying a comp at this point in time without getting the best stuff would be a financial mistake. People can't stay in the XP/DX9 mindset. It's changing and your gonna have to change with it.
Here's a comp I bought recently, and you'll be shocked at the price.
MSI P6N Nvidia nForce 680 based chipset
Intel Core 2 Duo E6700 2.6GHZ
2GB RAM (Being upgraded to 3)
2 x Nvidia 8800 DVI 768MB SLi Enabled
400GB Samsung Sata
Atrix 720Watt Silent Dual Fan
Creative Sound Blaster Audigy
Discovery X Case
Windows Vista Ultimate
That is the type of comp your really looking to buy. All for £1,800 including VAT, from Cougar Extreme. Shocking I know, if you had gone to Alienware or anywhere else it would have been double the price. If I were you I'de check them out - http://www.cougar-extreme.co.uk
Hope this helps.