I'd argue that a great movie is one that leaves its audience in astonishment and wonder. Personally, any movie that leaves you with nothing more than a few laughs or a stream of tears is just a negligible fad ( ahem, chick flicks ).
There are a bunch of movies I could think of at the top of my head that have left a lasting impression: Pulp Fiction, Fight Club, Shawshank Redemption, A Beautiful Mind, Life Is Beautiful, the list goes on. But there are two recent movies that have gone beyond leaving a lasting impression and changed my perspective on things, as ordinary and typical as they may be.
One of these movies being Limitless. Cheesy as it may be, I watched this movie at a point in time when I had the same ambition as the pre-NZT Eddie. It made me realize how, if I maintained my trajectory, I would reach none of my goals. Consequently, I began changing my habits and have since been on the road towards continual self improvement.
The second (and perhaps even cheesier) movie that has changed my outlook on life is Yes Man. It made me realize how shy and fearful most people are (think of the times you've said to yourself and others I should have , could have , and would have ). I definitely do not want to live a life of complacency and regret, thus being someone with an open mind and the bravery to try even the things that question my beliefs has allowed me to gain valuable insight.
If you haven't watched either of these movies I highly suggest you do. I'm well aware of the fact that these two movies are nothing close to revolutionary. However, they do convey a strong message that should be grasped by all.