room size

Tom, the smaller room is actually pretty good -- better in some ways than the larger room. You can expect some exaggerated bass at about 70 Hz, 145 Hz and 225 Hz. Apart from that, just be sure to get speakers that roll off quickly by 25 Hz -- you should be at least 3-6db down by the time it hits 25 Hz. The room won't naturally handle anything lower than that -- i.e., anything lower is in the pressure zone where things just don't sound natural.

Plaster and drywall is good -- keep surfaces stiff. An area rug on hardwood would be fine. You may want to get some first reflection point room treatments (just in front of the speakers on the side wall and, if you're adventurous, on the floor and ceiling) and bass traps in the corners. First reflection points on the floor are easy -- i.e., a rug or carpet. Then go to the side walls. If things still sound like they need improvement, go to the corners behind the speakers.

In terms of speakers, my experience would suggest that a pair of speakers with single 10 inch woofers would be fine. You could go as high as a single 12 inch woofer per speaker or two 8 inch woofers per speaker. Speakers with two 6 inch or smaller woofers should be avoided -- they will not provide enough bass for the room. HOWEVER, efficiency, design and taste have a lot to do with it so please, please do try to listen before you buy. Some dealers (even over the internet) will let you try before you buy. I know the folks at Montana do but feel free to check out others. There are lots of great speakers out there.

I am making the room smaller, the ceiling is 8 ft.yes exact, 12'6" X 15', I don't have to make it smaller, but it would make things easier and nicer, small cape cod, high traffic area, and 3 doorways would be eliminated with the down sizing. Plaster and drywall both. carpeting ,but hard wood underneath. was thinking of wood and area rug, but wall to wall is ok.

Donniebaker, few rooms are too small so long as you match the gear with the room and have the right acoustic treatments. Of course, the smaller the room, the less realistic bass you'll get. A few questions:

1) Are you actually making the room smaller or are you moving the system to a smaller room?
2) What is the ceiling height of the two rooms?
3) Are the measurements you give pretty exact?

I can run the measurements of the two rooms through a spreadsheet and give you some indications of the advantages and disadvantages. I'm assuming normal drywall and carpet in both rooms.