Mark,
We need more information to give you good advice. What is the make and model of both of your receivers and your speakers? Do you already have the speakers you would like to use in the other rooms? What are the other rooms, how big, etc.? Please tell us how many people will be using the whole house music system. What are their uses; background while working on a computer, enhancing their game playing, rocking the house down with parties? Is there a need for multiple source access in any of the rooms?