What are good brands for Home Theater sound systems?

I'm living with my "rich uncle" for about a year. It's a long story, please don't ask. He has put me in charge of setting up the sound system in his new home theater. He built a 25' x 30' addition on to the house exclusively for this. There is a large fireplace on the back wall. He runs a construction firm and a company that cleans the grease out of the hoods on fast food joints so he is kind of loaded. But he is also very busy. He set the budget at: "See if you can keep it under eight grand." As I have electronics experience I don't think I will have a problem hooking components up but when it comes to home audio my expertise is limited and my knowlege is dated. I have a nice stereo, a Vector Research receiver, JBL speakers and a Sony CD player so I guess that, and my experience in the Army Signal Corps qualifies me in his eyes as an audio expert. However I got that stuff a long time ago and I know most everything has changed in home audio / home theater or whatever they call hi-fi these days. Uncle has gotten himself a 60" (I think, - it's huge) TV, a baby grand piano and that's about it. Quite frankly he could just hire someone to do this but I'm pretty sure he is trying to prove something with me and keep me busy. He likes to have musician friends over and likes to listen to classic rock, jazz and classical so this will be a music system as well as a home theater system. Getting to the basic question; what are some brands to favor? What are some brands to avoid? I did some reading and I discovered 5.1, 7.1 and now see that there is a 9.2. I know what the numbers represent but when will the escalation stop and how many channels are enough?