Here's a more manageable business idea for ya...
As parents of small children, I'm sure we've all been to these Saturday afternoon birthday parties at various places...arcades, jungle gym type places, bouncy houses, gymnastics, etc.
So here's what you do...rent out about 4,000 square feet in some warehouse building - these places are all over and have plenty of occupancy available for a decent price. You deck it out with animal-themed decor from top to bottom, build a couple private rooms for the groups to have their cake and open gifts. Then in the main area you put some basic animals on display - probably nothing too exotic, whatever you can get your hands on that would be comfortable living there. Then you have a portion of the party where you, the animal handler, brings the animals out to the kids and lets them touch them, play with them, whatever. I'm obviously talking about safe animals here - puppies, kittens, lizards, turtles, snakes, ferrets, whatever. So one at a time, you go get the animal and all the kids sit in a circle and wait for you to bring the next animal out, tell them a little bit about it and let them pet it or hold it, etc. Have some other activities available like coloring or painting, etc for any down time they have.
Beyond you and your wife, you'd only need like 3 or 4 $9/hour employees to man the front desk and chaperone things a little bit...get some HS girls interested in teaching kindergarten some day and they'll work for nothing just to get the opportunity to work with little kids. You can borrow puppies and kittens from the animal shelter and I'm sure you've got ways to get your hands on some snakes, turtles, put in an aquarium, etc.
Zookeeper Gabe's Animal Party Palace
Genius!!
