You can save some money by ordering from scan.co.uk
Also, you forgot a power supply. Just a note, never buy a "cheap power supply". We have a Power Supply Guide
on the forums, but basically Antec and Corsair are your best bets. The corsair CX line is currently lesser quality than what we have come to expect.
Also, get Windows 64bit, this will allow you to utilize 4GB+of RAM. Another thing, the RAM you listed is a bit slow.
The case you listed will work, but the better known cases such as Cooler Master or Antec tend to be more durable and easier to work with. However, just about any case will work, you can pick the case.
Asus M4A78LT-M AMD 760G AM3
Coolermaster HAF 912 Plus
AMD CPU Athlon II 640
Windows 7 Home Premium 64bit OEM
Corsair Memory XMS3 4GB DDR3 1600 MHz CAS 9
Gigabyte GeForce GTX 460 OC 1GB
Corsair Enthusiast TX V2 CMPSU-650TXV2UK 650W
The total is £517.19 for the parts previously listed.