How to set up a Home Theater Network?

Could you please explain how one would set up a Home Theater Network? I've figured out resources to replace my satellite service, but I'm not sure whether to go set-top streaming or get a cheap PC or netbook.

Most of the articles I've read deal either with plugging a laptop into a TV or comparing various streaming/downloading channels, and the articles regarding cable-less TV are more than a year old on CNET. Streaming's come a long way in that time! I'd really like more information on how the whole system can be set up.

I have two main viewing centers which need to operate separately (one downstairs, one up). Does that mean I need two streaming sources or will one do the job (and how would that be controlled)?

How do I incorporate DVR into the system with an external, home-cloud hard drive?

My wireless network is a combination of wired and wireless. I'm hoping to have all the media sources connected with wires to improve performance since we have multiple internet users at any one time.

I know I've seen a LOT of comments from readers on various sites asking the same type of question, but no one really seems to know. I really think a How To on this topic will really help a lot of customers get the most out of cable-less life.

Thanks so very much!!