Rizzo,
On your room acoustics questions, you might try looking through Alan's
basement home theater article. One of his recommendations directly answers your questions, though there is more there worth reading as well.
Jason
Plan on Sheetrock or Wood-Paneled Walls and a Wood or Carpeted Floor
Avoid poured concrete floors and walls, which may cause boomy and exaggerated bass and degraded sound quality. If the floor is concrete, plan on covering it with a wood sub-floor and carpet to provide some absorbency. Likewise, cement-block walls should be covered with studs and sheetrock, drywall or wood panels.
