Panasonic SC-BT100/200/300 questions

[Hellhog]

I've been looking into getting the Panasonic BD60 and join Blu-Ray. I could get the player for $175 on Amazon. However, I don't want to use my 2.0 Shelf System for audio and my 5.1 Wireless Headphones don't really give that true surround feel. I'm trying to stick to a low budget.

Like I said I was looking into the BD60 and a seperate 5.1 system, but that would add up.

I was looking at the Panasonic systems:
SC-BT100
SC-BT200
SC-BT300

I noticed the 100 was discontinued and a 5.1 system (also is BD 1.1, the others are 2.0). However the other two are 7.1 systems.

My overall goal is to keep a low cost, play BD movies, upconvert DVDs, listen to movies in surround sound (either 5.1 or 7.1), and play my Xbox 360 in surround sound (only supports up to 5.1).

How is the 100 system? 200? 300? Does anyone know of any cheaper/better all in one systems that they would recomend (I can get the 100 for $380 on Amazon, 200 for $430, 300 for $490)? Will a 7.1 system automatically play like a 5.1 from a 5.1 source (as in automatically not use the extra 2 speakers)? My room is 12x10ft, is a 7.1 too large for this room size?