What needs upgrading? (+Spec Upgrade)

[Dharok]

Current Spec:
Intel Core 2 Duo E6300 @ 3.1GHz
2GB Geil PC-6400 800MHz
Gigabyte P35C-DS3R
Arctic Cooling Freezer 7 Pro
Coolermaster 650w PSU
Nvidia 8800GTX 768mb
250GB Seagate 7200.10
24" DGM Widescreen

My questions:

Is it worth going P45? (£99 Asus P5Q Pro)

Do I upgrade my air cooling and spend the extra on other components, or buy a watercooling setup (£150+)?

The 8800GTX, is it still good for new games on 1920*1200 res?

And finally, could anyone spec me a £500-600 upgrade.

 

[Dharok]

Thanks for the input there guys. I have had the same problem myself, not sure if I can warrant spending £500-600 yet not get much of a performance increase.

Any idea of what I could expect for my money next year if I were to save it?