first of all let me say im new to the home theatre thing so if my ?'s sound basic and stupid, sorry. im looking to get the onkyo txsr701 for my axioms (m60's,vp160,qs8's(3)) 6.1 setup that will be coming soon. ive seen so many different fomats for surround shopping for receivers could someone tell me what they all are, the difference between them all (dolby digital, pro logic, etc...) particularly the formats the 701 receiver have. it says thx ex, are there different types of thx surrounds?

also, ive heard alot of talk about sacd's and dvd-a. dvd-audio is just a cd on a dvd that will play in any dvd player right? do you need a special cd player for sacd's or will they play in any cd player? im a huge pink floyd fan and cant wait to hear some cd's on the new system.
thanks in advance.