Reb, 1. is pretty clear: if possible, have the tweeters at or just below ear level. Raising the M22s about 16"-18" is about right, and also puts them about at the middle of the TV screen, although this isn't critical. The VP150(if it's going to be on top of the JVC)might be tilted slightly forward so that the tweeters point right at your ear level.
You haven't described your room and 2. isn't clear to me. You appear to imply that all 3 surrounds will be mounted behind you on the back wall. The 2 side surrounds should give you a side surround effect and the back surround a back surround effect. If for some reason it's not possible to mount or at least aim the sides to the side walls, then they should be separated as widely as possible, to give a bit of a "side" influence to the sound pattern. Height can be about 6 feet.
Again, not critical, but normal seating height puts your eyes roughly level with the middle of the screen on your 4' set.
