Fanless low power FC10 build: Please check my specs

Hallo everyone,

This is my first HTPC. I've researched a lot and this is the result. I want it to be fanless, low power and work well with Linux/Ubuntu. According to many many reviews, these components should work together not exceed 30W in idle.

Mainboard: Intel DH77DF ??
CPU: Intel i3-3220T
Case: Streacom ST-FC10B Black
Case Cooler Adapter: Streacom ST-HT4 Heatpipe Adapter für ST-FC9/STFC-10
RAM: Samsung MV-3V4G3D/US DDR3 1600 2x4GB
PSU: ??
1x SSD: Samsung MZ-7PD128BW SSD 840 Pro 128GB
2x HDD: Western Digital WD Red 3TB WD30EFRX
1x BD Drive: Sony Optiarc BD-5850H

What do y'all think?

I do have a couple of questions, however:
1. PSU: I have no idea what PSU to choose. Pico PSU, I guess?! But which one?
2. PSU: The PicoPSUs I've looked at can only connect one SATA. How do I connect the 4 drives in my build?
3. Mobo: There are so many possible boards. This one is basically chosen at random. Do you have any other suggestions?
4. Building it: As I said, this is my first HTPC. What else do I need to order? I'm talking about stuff that y'all would think about, but a first-timer would forget :-)

Cheers,
Philipp