Remy – Dawn of the Dead (Original)
Remember – we are talking about those old-school zombies that are slow as hell, falling down as they are trying to get you. Not the remake zombies, which have all the running skills of Usain Bolt. My fat ass would not last a second in that world, but in the old school zombie world, the answer is easy, and made even easier if you are at a mall. You just go to the sporting goods store (which clearly they do show in the movie), get all the treadmills, set them up to run on the main power source in the mall, and you line the outside wall with them, facing outward.
Come on, we have all seen the memes and pics on the web that show this idea, and it is simply brilliant. I also firmly believe, if you watch the old Romero series, it is implied by Day and Land that the zombies start to remember, and they get conditioned to certain behaviors, so once they got shot off treadmills for a day or so, they would have realized they had no way of getting to their food source, and eventually just stopped and moved on. You see on multiple occasions that it is implied electricity is still on, and so as long as you have that for a few days, you can secure that mall. On top of that, the mall itself would have proper provisions to last a long time in a post apocalyptic world.
Treadmills, a zombie’s worst enemy.