Right, that gives it a bit more focus. I've played all of those on my PC you see, so I'm kinda familiar with that side of things - BF2 has taken up a large chunk of my spare time over the past few years!
That PC looks good, but I have a couple of concerns. The only problem is that on both counts, the price will rise, so obviously they're only recommendations - I know the price can be difficult.
Basically, that power supply has me extremely concerned. It has a high output of watts, indeed, but at £20, it's a very cheap package. Cheap Power Supplies may sometimes work, but at other times they are just an utter liability - I really wouldn't take the risk with your brand new system. I would advise that you go for something with a name, 600W will probably leave you with some headroom, but that's always a good thing. I'm currently using a 580W Hiper PSU, there's one on overclockers right now for £48.
http://www.overclockers.co.uk/showpr...id=123&subcat=
There are obviously others on there that would be fine for you to use, just please don't go for a cheap option because if there are problems, you risk destroying a lot of expensive components.
And with respect to the graphics card - you mention SLI, I don't know if that means you're planning on buying two. But, as a general rule, if you plan to buy two mid-range cards, put the money together and buy one top-range card, and it'll be far better. And for gaming, especially things like Crysis, you will probably be disappointed with anything lower than an 8800. On overclockers.co.uk
An 8800GT would set you back £135
An 8600GT would set you back £70
But you'll get way more than double the performance from the 8800GT. The 8600 series isn't really for the latest games, it'll get by, but it won't be the best.
Anyway, it's up to you, just my personal opinion. The rest of the rig looks fine, 1gb of ram should be fine, and you'll always have the opportunity to upgrade later.