Hi, I'm getting my very first home theatre system, and am on a *very* tight budget. I would just like to get one of the off-the-shelf HT packages. I know there are sets from a 100W total (probably 20-30 W per channel) to 750 W and beyond. My question is, how much per channel do I really need at a minimum to have a reasonably happy movie-watching experience without having to have my ears glued to the speakers? Will I be happy with a 105 or 150 W system? Thanks.