Whole house wiring
I would recommend running Belden 14/4 = 14 AWG / 4 conductor (or 12/4) from the A/V closet to the volume control in each room and 14/2 from the volume control to each speaker. If you want to use a sophisticated distribution system with keypads, multisource, IR sensors, etc. then also run cat5e to each of the volume cotrol boxes.
Westlake Electronic subbly is a good source for bulk belden cable by the foot for about 20 cents a foot. Try the Belden part #s below.
5103UP = 14/4
5100UP = 14/2
5000UP = 12/2