I may or may not be showing my shallowness here, but I don't like describing or categorizing films all that much, even in a very general way.
For example, I would say A Clockwork Orange "is about" the way you can't change how a person is and how they think. But really, I look for even more simplicity than that in film.
Another example. I once let myself get into an argument over the merits of Full Metal Jacket. The other guy was saying something like "It's essentially about how hard it is to perform a mercy killing, something that Aliens accomplished in a 2 minute scene." I was like, "What?". And I guess that's why I don't like looking for meaning in just about every movie I see, i.e. I don't want to presume to know what the director intends, as it can often negatively affect my judgement.
That could certainly just be me and my still developing appreciation for film (and I hope it keeps developing for a long, long while yet), but that's how I am at the moment.