New LAMP + NAS server build

You guys have given me great advice in the past, so I thought I'd try again with a new system build.

Goals:
cheap
low-energy
quiet

Purpose:
Primarily, this system will be a LAMP server (Linux, Apache, MySQL, PHP) for my personal development projects. It will also serve as a CVS server and repository. I want to leave it up 24/7.
Secondarily, I thought I'd set it up as a NAS server as well.

OS:
Ubuntu 9.04 server edition. This will be a headless system, so no video card or sound card is required.

Components that I'm considering:
Case:
I'm leaning toward this case: Antec New Solution NSK2480 Black/Silver 0.8mm cold-rolled steel MicroATX Desktop Computer Case 380W Power Supply - Retail
but I was thinking of this one as well:Antec NSK 4480B II Black 0.8mm cold rolled steel for chassis durability Computer Case EarthWatts 380W Power Supply - Retail

HDD:
For NAS: 2 x Western Digital Caviar Green WD10EADS 1TB SATA 3.0Gb/s 3.5" Internal Hard Drive - OEM in a RAID 1 configuration. Although, for the low-energy portion of my requirements a single hard drive may be sufficient.
If I decide to skip the NAS then I'll use a single smaller Caviar Green.

Mobo:
Either the GeForce 8200 chipset: ASUS M3N78-VM AM2+/AM2 NVIDIA GeForce 8200 HDMI Micro ATX AMD Motherboard - Retail

or the 760g: ASUS M3A76-CM AM2+/AM2 AMD 760G Micro ATX AMD Motherboard - Retail
I was also considering a 780g chipset, but those are a bit more expensive.

Memory:
G.SKILL 4GB (2 x 2GB) 240-Pin DDR2 SDRAM DDR2 800 (PC2 6400) Dual Channel Kit Desktop Memory Model F2-6400CL5D-4GBPQ - Retail

[CPU]
AMD Athlon 64 X2 5050e Brisbane 2.6GHz Socket AM2 45W Dual-Core Processor Model ADH5050DOBOX - Retail

Have I missed anything? I was considering different CPU coolers, but I'm not sure what may fit in the case and if it will be any quieter than the one that comes with the CPU.

Thanks in advance for your help.