A) You'll want to look into cablecard solutions. These devices, when paired with a cablecard from your cable provider turn your PC into set top box with DVR capabilities.
B) I would probably consider, given your current hardware, an external NAS solution.
C) That is going to depend on the content. If it's protected in anyway (say a protected television show tagged copy-once), you'll only be able to view that recorded content on the device it was recorded on. If it's not protected, then you should be able to view it anywhere it's available. It's been my experience, that most television programming is marked copy-freely, which means once it's recorded, I can do pretty much whatever I want with it. Only some programs (probably sporting events and pay-channel movies/shows like HBO) are marked copy-once.
D) I'd stick with Windows 7 for this idea, unless you want to build two separate systems.
What I have in mind:
First - Complete your HTPC Build:
Case/Power Supply:
hec Micro ATX Media Center 300W Power Supply / HTPC Case - $59.99
Motherboard:
MSI 880GM-E43 AM3 AMD 880G HDMI Micro ATX - $0.00
CPU:
AMD Phenom II X2 550 Black Edition Callisto 3.1GHz Socket AM3 - $0.00
RAM:
G.SKILL NS 4GB (2 x 2GB) 240-Pin DDR3 SDRAM DDR3 1333 - $22.99
Hard Drive OS: Western Digital Caviar Blue 500GB - $0.00
Hard Drive Storage: Western Digital Caviar Black 500GB - $0.00
Optical Drive:
ASUS DRW-24B1ST/BLK/B/AS - $18.99
OS:
Microsoft Windows 7 Home Premium SP1 64-bit - OEM - $99.99
Optional:
Graphics Card:
ASUS EAH6450 Silent/DI/1GD3(LP) Radeon HD 6450 1GB - $42.99
Now your Add-Ons:
NAS Storage:
1 - 2 x Sans Digital 5-Bay USB 3.0 / eSATA Hardware RAID5 Tower Storage Enclosure - $269.99 - $539.98
Hard Drives:
1 - 10 x Samsung EcoGreen F4 2TB SATAII - $119.99 - $1199.90
Remote Control:
Windows 7 Certified MCE IR Remote Controller - $25.99
TV Tuner:
Hauppauge WinTV-DCR-2650 - $99.99
Dual Tuner Cablecard device. Connects to your HTPC via USB.
SiliconDust HDHomeRun Prime 3CC - $179.99
Triple Tuner Cablecard device. Connects to either your HTPC or your network (To share tuners with other networked devices).
Ceton InfiniTV4 USB - $184.99
Quad Tuner Cablecard device. Connects to your HTPC via USB. Tuners can still be shared among other networked devices.
SiliconDust HDHomeRun Prime 6CC - $379.99
Six Tuner - Two Cablecard device. Essentially two if the HDHomeRun Prime 3CC devices in one.
The Reasoning:
The 880G north bridge of the motherboard should provide you with enough graphical power for HD Video playback. If now, then you can add in the graphics card later.
I wanted to keep the HTPC itself smaller, so I went with the small form factor HTPC case. With an external storage solution, there's not much need for a larger case for more hard drives. In fact, the only add-on card I see being installed into this system is the NAS controller card.
I didn't see any 10 Bay External Storage solutions and you'd probably need a Full Tower Case in order to get 10 internal Hard Drive bays. I figure one of the 5 bay external storage solutions plus a couple 2TB hard drives would be enough to get you started. You can add on to them later.
The TV Tuners:
Since your selected motherboard only has one PCI-Ex1 slot and that is going to be taken by the external storage controller, I opted for external devices. The only real differences between these devices is how many tuners each has and the method of sharing tuners with other networked devices. Again, these devices, when paired with a cablecard from your cable company, turn your PC into your set top box. The only difference is you can no longer order PPV movies/sports or On-Demand.
Hope this helps.
-Wolf sends