Interesting how we are the "Garden State", yet any attempt at homesteading is shot dead on arrival. I'm in Wayne, and I can legally own chickens with reasonable constraints. The animals cannot be within 25 feet of the property line and whatnot, and if you do things correctly, you can raise a large number of birds in a small area. My opinion on the issue here varies. To start, I think you will be much better off trying to fight and change the current law than this "house-pet" charade that you are going to prove. I mean realistically, you have an excellent story. You have built an excellent coop for the birds and you keep them for the sole purpose of obtaining eggs and raising them as pets. They're essentially an outdoor cat with benefits. Two things that you must do going forward though...
ENCLOSED RUN: You kind of walked into this one. Assuming that every neighbor enjoys a chicken walking on their property and scratching around is certainly not a good idea. All it takes is one person to call and say there are chickens roaming the neighborhood is enough to get them taken away, as you've learned. Did the summons specify if somebody called, or if the animal control was just in the area at the time?
COURT BATTLE - The zoning laws seem to specifically target commercial farming, and they make the assumption that what you are doing is a large scale farm. A picture of your coop, as well as your family with the birds will change that connotation immediately. Do not live with these unjust and ridiculous laws. What you are doing is a GOOD thing. You are raising your own food. It is your own right! You can have a garden, but you can't have a small chicken coop? You can grow tomatoes, but not eggs? What you have to do here is advocate and explain to your town why an animal that needs roughly 2.5 square feet of indoor space and 5-10 square feet of enclose outdoor space should not be raised on 5 ACRES. That is bogus right there. Petition. Effectively, you have to put your money where your mouth is and prove that other people don't mind, and actually think what you are doing is great (because it is). Chicken owners are proud people, and the thought that we should live in the country if we want to raise our own food is absurd. Take it to court, but don't conform to their standard! Show Denville why they are wrong. Use examples of other NJ towns along with your own personal story. Be the change here. If you merely try and win on their rules, they will find a way to beat you. Please try and contact other chicken owners in the area. We had some very brave people in Wayne who challenged the town, and they won! Essentially one man changed the way our town thought about chickens, and now I can happily raise them! Best of luck to you! Please let me know how this goes!