Home Sound System Question

Hello Everybody!

I want to replace the existing Bose 321 system as we just can't her it too well from about 10 feet, especially the dialogues and other mid-tone sounds! It also is not the best system to listen to music. I am looking at streaming music from Spotify and iTunes etc.

I am working on setting up a home sound system with a minimal gadgets and decent quality (not looking for a very high end system). I want to setup a efficient sound system for the TV, as well as in another room setup a 2-speaker system for just music.

Here is what I am thinking of:
- Receiver: Denon AVR-1913
- In-Wall speakers for music: Boston Acoustics HSi 275
- In-Ceiling for TV: Boston Acoustics HSi 250

Here are the questions:
- What is the best setup for the TV speakers? 2, 4, 5 or 7 speakers? Are these ones mentioned above a good choice (Boston Acoustics HSi 250), or there are better ones out there in the same price range? Is In-Ceiling better than In-Wall? I want to make sure the sound is clear.
- Any opinion on the Boston Acoustics HSi 275?
- Is the choice of the receiver good?

Much appreciate your inputs. Thanks!