Hello hellarda, your specification looks fine on the whole. However, I would question some of the components that you have chosen.
Graphics Card:
The Nvidia 9800 GTX is actually just an overclocked Nvidia 8800 GTS 512 and isn't worth the price premium in my opinion. The Nvidia 9800 GTX also looks very unattractive since you can now purchase an Nvidia 8800 GTX for around £30 less which is a better card overall especially at the resolution that you are looking at playing games.
CPU:
The CPU that you have chosen is quite expensive and you could save quite a bit of money by choosing the Q6600 instead which when overclocked would perform exceptionally well.
Power Supply Unit:
You don't really need a 700 wattage power supply unit unless in the future you are looking at running a massively overclocked, two high end graphics processing units and a dozen hard drives.
Memory:
The memory that you have chosen is fine. However, you could purchase 4GB of 6400 rated memory for slightly less and the performance hit would be unnoticeable. Though, you will need a 64-bit Operating System to be able to utilise all 4GB of RAM.
CPU Cooler:
Once again the CPU cooler that you have chosen is fine. All though, it is fairly expensive and something like the Tuniq Tower which is slightly cheaper would be more than sufficient.
Taking the above into account, I have just put a specification together to give you another option to look at:
