Checkout Irina Markova and her poodles from the Conan O' brien show for inspiration. Irina performs with the Big Apple Circus. Be sure to notice that the dogs are performing quite happily.
Just a quick word of caution here. It is very hard for dogs to walk on their hind legs. Not all breeds were meant to do this and it takes a long time to properly condition even those that seem to have the knack for it.