looking at those specs, your building a gaming pc?
For gaming I think that it should be a recommended 1gb of RAM, so probably go with 2x512mb OCZ Ram, pc3200
Other than that looks sweet!
Oh wait, maybe another 120gb HDD...
Intel Core 2 Duo E6400 *Cooled with Thermaltake Mini-Typhoon* || Intel Quad Core Q6600
2gb Kingston 667 DDR2 RAM || 4gb Kingston 667Mhz DDR2 RAM
Gigabyte 512mb 8800GTS (683/2150)
250gb Seagate HDD (ATA133) 7200rpm/16mb cache || 750gb SATA2 Seagate HDD
ASUS MW221U 22" Widescreen 2ms.
Logitech Z-5500D 5.1 Speakers
Creative X-fi Xtreme Gamer Fatal1ty edition
3DMark06 Score = 8524 (1280x1024)