Can anyone tell me if this system setup is a good idea?? Any advice??

[b]I am building my own system for the very first time and I THINK I have a pretty good understanding of the components I am getting, but I want to be sure that all components will be compatible and if they are all good quality - meaning I don't want one thing lagging down the rest. Any comments or advice about my new build would be appreciated.
[b]
This is my setup:

Azza Solano 1000 ATX Full Tower Case w/ tons of fans

AMD Phenom II X4 965 Denab 3.4Ghz Black Edition Processor

MSI 790FX-GD70 AM3 ATX 2600Mhz HT DDR3 2133OC Quad PCIE2.0 Motherboard

A-Data 8Gb (4 x 2Gb) 240 Pin Dual Channel DDR3 1600Mhz PC312800 Memory

Dual (2) HIS H467QS1GH ATI Radeon HD4670 1Gb 128Bit DDR3 PCIE2.0 Crossfire Linked Graphics Cards

Western Digital Caviar Green 750Gb Hard Drive

Toshiba External 320Gb Hard Drive

Sony 24X DVD-RW Burner w/Lightscribe

Sony 22X DVD-RW Burner

Tuniq Potency 750W SLI Certified Power Supply

Thermaltake SpinQ CL-P0466 CPU Cooler

Aerocool All-In-One Media Card Reader/USB Hub/Audio Ports 5.25"x1

Xion Xon-MTR002B LX Flip Up LCD Thermal Control Display 5.25"x2

Windows Vista Ultimate 64Bit Edition

Hitachi 37" HDTV Flat Panel LCD Monitor

Windows 7 comes out in just a few days so get that instead. Also, I second a better hard drive as the primary drive. Crossfiring 4670s leaves little room for upgrade later. I would recommend spending the same amount on one card right now and a little later buying a second. That processor might be overkill. That power supply is definitely way more than you need. Get a 650w for much less.