The Laws of Biology, I am disappointed in seeing your post. To assume something good someone does for others is altruist shows how much altruism does infect our culture. Before getting into the movie, know that Ayn Rand said that true benevolence can only be done selfishly. It's altruism that destroys our capacity for benevolence. I think in real life, things done to help others is rarely what is altruist. The altruist things that are most common are when an employer keeps an employee around who doesn't produce or a friend has a friend he doesn't like or when a person votes his conscience, something like that. Listens to his mother because she's his mother. Most people don't give to the Salvation Army because they feel they need to, they feel good about donating.
Next, I would argue there are very few movies as heroic as The Shawshank Redemption that fit the principles of Objectivism. Also, the context was spot on. Reason is the key even in the most hopeless of contexts as this movie illustrated. You should value this movie because it could hardly be more Objectivist if it tried.