It's usually a little awkward using any receiver for zone 2. I'd really recommend a separate receiver to run the whole house. Denon makes a couple great receivers that will do the job nicely. You will still need an impedance matching speaker selector. Control systems such as Niles or Xantech with keypads in each room will help. Lots of research from there and it can be done on the cheap or for several thousand. Yep, it is sometimes cheaper, easier and less complicated to buy a system for each room.
I do use my whole house system daily.