I would drop the GSkill and get the
OCZ 4GB (2x2gb) on this week only - it'll save you a few quid and will be just as good.
The PSU is a major overkill for a system with a 8800GT, it's even a major overkill for a system with a more power hungry graphics card. Unless you plan on going Crossfire/SLI in the future then I would just go with something smaller like the Corsair HX520W. Your system you've spec'd would be easily ran by the HX520W.
Case is a bit lavish, but it's your prerogative

I have myself went for the flashy case sometimes, but if you wanted to save yourself some money then you could just drop it down to something like the P182 which is a brilliant case.
Quad is fine, handy for Photoshop.
Motherboard is okay, but if you aren't planning to use the specific Deluxe features then I would just go with the PQ5 Pro. If you do plan to Crossfire at some point if you changed to a ATI card, then I would skip the PQ5 and get a X38 board as they have dual 16x PCI-E 2.0 lanes, rather than dual 8x PCI-E 2.0 lanes.
DVD Writer is fine.
If you aren't planning to overclock then I would just drop the Noctua and just go with something like an Arctic Cooler Freezer 7 Pro which'll keep you cool and quiet. Even if you were planning to overclock I would just drop the Noctua and get a Tuniq anyway.
From reading what you want on hard drive, you basically want a reasonable space for your system drive which'll be in a Raid0 array for speed, and then storage drive. I wouldn't go with 3x Seagate 7200.11's for this, and instead I would opt for: 2x WD AAJS 160gb's, 1x Samsung F1 750gb. Getting those are £10 more expensive than the 7200.11's but I believe they'll suit you much better and overall are faster than what you proposed. With the new setup, you'd have some WD AAJS's in Raid0 @ 160GB, and a Samsung F1 for storage @ 750GB.
My proposed spec and changes: