CPU: If it was me, I'd either get the E2160 and Overclock it too 3-3.2GHz which it fairly comfortably or fork out for the Q6600.
Motherboard: You shouldn't really be a fan boy for anything when coming to selecting computer components, get the best on the market at that time, for instance their were a lot of AMD fan boys but despite that you'd wanna get an Intel C2D as their ATM the best CPU's on the Market. Unless you need all the added features of the P5K deluxe then I'd opt for a cheaper one, all the P35 Boards are good, or get the Abit IP35 Pro for cheaper which is highly rated and recommended.
RAM: I'd have a look at the;
GeIL 2GB (2x1GB) PC6400C4 800MHz Ultra Low Latency DDR2 Dual Channel Kit
£49.99
£58.74 inc VAT
as its rated at the same speed and a lot cheaper, although the ballistix are meant to overclock like a beast.
GFX Card: Good choice if you game at 1680x1050 or higher otherwise the 320MB Version should be sufficient although the 640MB version is still a good choice even at lower res's if your planning on keeping it for a while.
Hard Drive: Good choice, the WD's AAKS are currently some of the fastest yet quietest hdd's on the market.
CPU Cooler/Cooling: Although theirs nothing wrong with you chose and your an Asus fan boy, I'd look at the Tuniq Tower for the same price although their currently out of stock with no ETA.
You wont need the extra Akasa fan, honestly ... the Antec 900 has plenty of cooling.
Sound-Card: I'd possibly look at the X-Fi XtremeMusic edition sound-card as don't be deceived by the fact it has the word "Gamer" in it and therefore better at games than the Music version.
Case: Excellent cooling, probably the best in its price range and does look fantastic in the dark, could maybe look at the Antec P182 for a few pounds more, better cable management and more room.
PSU: Not a lot to say, one of the best PSU's on the market.