My head is spinning with possibilities for HTPC...

Over the past few days I've read and read and read stuff about a HTPC. Unfortunately, the more I read to narrow down my options, the more I come away with more options!

OK, back to basics: what's the requirement?

• Mainly stereo audio usage (90%) via SPDIF - I'll be adding 2 x SotM SATA filters one to each HDD (see below for what the HDD comment is all about).
• About 10% video usage (No 3D requirement - I don't have or plan to have a 3D TV for a few years)
• Support for Netflix (1080p), and the UK terrestrial streams (iPlayer, 4OD, ITV Player, Sky etc etc)
• Must be "silent" (or so quiet as to be inaudible in a lounge)
• Here's the odd one: It's a occasional use NAS server as well. Basically, I store about 3/4 TB of non-audio/video "stuff" which I access occasionally. This stuff must be RAID 1 protected.
• It must be mini ITX form factor.
• HMDI, Optical Digital out (not via USB).
• Controllable via a remote. (Android would be nice to control it - we don't have any Apple in the house at all.)
  

I've read the two main stickies on this forum and I see two things that stand out:

1. I'm a "group 6" person I think
2. NAS plus HTPC isn't recommended but if I must, the WD Green HDDs it is. So, WD greens it is then.
   

Originally, I was looking at fanless mobos but then I got bogged down into AMD v Intel v Nvidia. Barebones boxes - none of which seem to support 2 x HDDs AFAICT, so I am looking to build my own. (I'm OK with that: I have been building PCs since WFW 3.11.)

I could say "so, here's what I am considering - any comments", but I'd end up listing every mini ITX-based system on the Internet!

I know it appears lazy to ask, but could someone at least assist me in narrowing down the options please?

TIA

EDIT: Don't care about the OS. I'm comfortable with all of them.