im going to upgrade to this spec in a couple weeks is there anything u can see that needs changing?
Asus P5N32-E SLi nForce 680 (Socket 775) PCI-Express DDR2 Motherboad(£152.74)
GeIL 2GB (2x1GB) PC6400C4 800MHz Ultra Low Latency DDR2 Dual Channel Kit (GX22GB6400UDC) (£135.11)
Antec Nine Hundred Ultimate Gaming Case (£65.79)
Arctic Cooling Freezer 7 Pro CPU Cooler (Socket 775) (£16.44)
BFG GeForce 8800 GTX OC 768MB GDDR3 HDTV/Dual DVI (PCI-Express) - Retail (£387.74)
NEC AD7170S Serial ATA 18x18 DVD±RW Dual Layer ReWriter (Black) - OEM(£22.31)
Intel Core 2 DUO E6600 "LGA775 Conroe" 2.40GHz (1066FSB) - Retail (£193.86)
Asus P5N32-E SLi nForce 680 (Socket 775) PCI-Express DDR2 Motherboad(£152.74)
GeIL 2GB (2x1GB) PC6400C4 800MHz Ultra Low Latency DDR2 Dual Channel Kit (GX22GB6400UDC) (£135.11)
Antec Nine Hundred Ultimate Gaming Case (£65.79)
Arctic Cooling Freezer 7 Pro CPU Cooler (Socket 775) (£16.44)
BFG GeForce 8800 GTX OC 768MB GDDR3 HDTV/Dual DVI (PCI-Express) - Retail (£387.74)
NEC AD7170S Serial ATA 18x18 DVD±RW Dual Layer ReWriter (Black) - OEM(£22.31)
Intel Core 2 DUO E6600 "LGA775 Conroe" 2.40GHz (1066FSB) - Retail (£193.86)
I'd go for a Tuinq Tower rather than the Arctic. Better quality control and realllly good temps on those beasts 
Get the 520watt if you cant afford that, or the 550w Antec if modular doesn't bother you.