Oops forgot to mention because of the course I'm on at college i have access to the Microsoft Developer Network Academic Alliance and i have access to XP home, pro, Vista Home, Ultimate and Windows 7. My plan is to use windows 7
The machine you've specced there seems decent enough for the price, but don't expect to max out newer games with that video card (which is about 3-4 years old tech now).
Would you be comfortable building a machine yourself?
If so, I'd urge to go with an AMD system, as at the moment you get a lot more for your money, particularly for gaming, where the CPU makes very little difference at 1920x1080 (I assume thats your screen resolution).
Go with a Phenom x4, and try to get the fastest vid card you can, a HD4870 or HD5770 for quite cheap would be streets ahead of the GTS250.
Without spending time checking through online prices right now, I reckon you could build a faster machine for the same money or even a little less.
I've never heard of that supplier before, and by the looks of their site, I wouldn't touch them with a barge pole.
Check out tekheads.co.uk, dabs.co.uk , overclockers.co.uk and komplett.co.uk
I've dealt with all in the past and found them very good. (and some may have collection points near enough to where you live).
Lancool PC K62
Phenom II x3 @ 3.5Ghz
ASUS GTX570 DirectCU II
I'd only be using it for Counter Strike Source and potentially EVE-Online. The main issue with this supplier is the convienience tbh my friend; with regards to AMD and ati issues i;m more confident using Intel Cores and Nvidia GFX cards as i know them far better. Despite the fact i've used an AMD dual core previously
Dublin is right about the videocard. I used to own a 9800GTX+ which is exactly the same card as the GTS250 and trust me, you don't want that. Even one 4870 blows it away.
Did you say the HD5850 is only 20 more than the GTS250? That can't even be right, be sure to check the prices again. The HD5850 is one of the best cards out right now and if you CAN get it, make sure to do it! It will easily max out just about any game right now.