thanks for all the responses.

my tv room:
side to side is 15ft
from back of couch to the tv wall is 15 feet.
as for high, my ceiling is slanted. so
1.) high of tv side is 8 feet.
2.) high of back of couch is 14 to 15 feet. However, behind my couch is a wall that goes up only 5 feet. the rest is open space that connects to my living room (2nd floor). essentially the tv room is partly connected to the dining room on the side (so some open space) and the living room (at the back of couch, see above).

1.) we also have a technics stereo reciver sa6x550 and 2 surround sound speaker (sb-s27), two large front speaker and one center channel speaker (sb-afc31). Now they are pretty old (atleast 10 years old). Can i still use any of them or should i just get rid of the whole thing????

2.) can anyone tell me how the theater system is going to benefit me when we just watch regular tv or HDTV. How many speakers do we need to utilize to watch a High definition Hocky Game or a Movie on TV (like fox network or etc)???

3.) i am thinking of spending around $2000-2400 u.s.(5.1 system with a reciver). To be honest, i do not plan on reselling the item i have purchased. so i am cautious of what piece of item i buy as the home theather system will last me atleast 9 years. i would like to start off getting a good receiver. Sort of get my feet wet and see where it goes. as i figure i can aways buy additional speakers once i experience what i have. I am hoping people could suggest a couple of good receiver, good brand and good speakers, subwoofer, etc.

thanks for the help