I live in a gated community. There is a mini-mall behind it, with a gate between the two. The mall has a Publix, several bakeries, a Home Depot, and a gun store (along with an ungodly amount of clothing stores and banks). Each store has its own generator, and I myself have a small generator.
My Plan: Since there is about 50 feet of distance between the community and the mall once you exit the gate, I would work on fortifying that area with a wall of some sort I made from planks from the Home Depot. Travel between the wall, and go to the gunshop and get some guns. I'd leave some lying around at various points in case I ever get cornered, so I have emergency weapons already at certain points.
Use many of the generators' leftover fuel powering the Publix' generator for protection of the food supply. Move food from the bakeries to the Publix. Every night take pot shots at the zombies. Eventually,due to lack of food supply we will expand into the neighboring areas.
About two miles from here, there are several patches of land we can grow food on, we'll cultivate it and grow whatever fruits and vegetables we can. We'll be surviving, albeit not by much, but we could take the world back, slowly as it may be.
Flaws: At any given point in this plan, there is a possibility of being overrun.
We could easily run out of ammunition before we run out of food, and then we could be screwed (assuming no one in the community can make bullets out of paper clips, I might add).
I'm not very proficient with guns.
If there's not enough fuel in the generators, we would have to move on with expansion before we have enough people, or even worse, before we have enough time to even get set up.