Intel Core 2 Duo QUAD CORE Q6600 Processor
If you don't overclock I'd suggest you get a E8400 or E6850 if it's not available. If you overclock, stick with the Q6600.
8192MB Corsair DDR II 667
I doubt you need 8GB of RAM. What are you using this computer for and will this be a 64bit OS?
1000GB SATA II Seagate Data Storage RAID Stripe
I do not recommend RAID for a consumer based PC.
NEC 7200 Multi Format DVD/CD ReWriter
I suggest getting a Pioneer or samsung drive instead.
nVidia 8800GTX 768MB
This GPU is at the end of it's life, it has been replaced by the 8800GTS 512mb (G92 core), which is significantly cheaper and for the most part outperforms the GTX.
As for how well this will run with Crysis, what resolution do you intend on playing at?
James