One running theme in this thread has me worried: the pernicious idea that previous or ex-post reading can be detrimental to one's ability to construct an understanding of a movie or to be able to react to it honestly. I wholeheartedly disagree with the notion.
I generally avoid to read reviews before watching a movie so as to not spoil the experience - and that is not the sort of thing I am talking about here. Reading someone else's take on the film after having experienced it can only further one's understanding of it, be the writer a professional critic or an amateur.
To cite an old philosophy teacher of mine, there is no idea more wrong in philosophy than believing you should not read philosophy books before forming an opinion on a question for fear they will pollute your thinking and make it less pure in its individuality. Now, the analogy is not perfect, and unlike philosophy, you can think about a movie in a vacuum because the exercise is usually one of analysis of an object whereas philosophy is abstract reflection on ideas that do not present themselves in their entirety by a similar process to that of watching a movie ; but the principle still stands.
That distinction means that it is not necessary to read about a movie to form an opinion about it. That is because we are able to apply whatever tools are at our disposal to poke it and dissect it, even in a vacuum. With no information about the history and tropes of the genre, about adapted material, about the filmography of the director, there are always things we are able to think about, depending on how we are equipped - although arguably, an actual utter lack of knowledge about anything would make us tool-less. Another reason we can write about the movie in the vacuum is that we have an emotional subjective reaction to most movies. Even if we understand nothing at all about a movie, it can still frighten us, make us laugh or cry, or excite the hell out of our living nerves. Maybe we will not be able to say how or why ; but the description of the reaction remains available.
Since we are not industry professionals, we have no obligation, and I am guessing no time (not to mention, probably, the inclination) to read about every movie we watch. That is fine, no one is here to become an established critic. However, reading other people's takes can only enhance our view on a movie.
Personally, I usually read reviews after watching a movie in three instances: if I am having trouble formulating my opinion of it and am looking for someone to supply me with their eloquence, if I didn't understand the movie and need some light to be shed upon it, or if, aware of what my own opinion is, I am merely looking for a critic to compare notes with, whether to understand his disagreement or have that tap-on-the-shoulder feeling that comes with reading things we ourselves think. I am mostly going to repeat things said by Junior as I talk about how we can completely reject an article we disagree with or adapt a criticism to our own take on the movie to further and sophisticate the latter.
I will try providing a few examples, all coming from RogerEbert.com articles, which is my go-to place for movie criticism. I just watched The Conversation and Blind. Both baffled me a bit and I am going to look for some enlightenment on their meanings and some plot points that are not entirely clear to me. My objective is understanding the movies more clearly before I produce a review, even though I have a good idea of what my reaction to them is. I would rather not write from a place of ignorance. I am confident that I will not immediately believe i the interpretations of the writers because I have a history of disagreeing with reviews. I thought Ebert was too harsh in criticising Dirty Harry for being fascistic and in his review of AI it was evident that we viewed artificial intelligence in fundamentally different ways. I went to the website before writing about The Treasure of the Sierra Madre because I could not put my finger on what made the movie good. I wrote an opinion, an excessively poor one, and Ebert was, naturally, infinitely more eloquent than me. We didn't focus on the same subjects though. We rarely do. That is another wealth you acquire with reading other people. Two other contributors than me here wrote about Meek's Cutoff for Jeff's month. None of us came at it from the same direction and Sandy focused on thoughts about the colonist experience that spoke to her sources as an American and lover of Westerns. My thoughts were more ethereal. I was glad she reminded me of more down to earth considerations about the film.
The corollary of reading a review should be critically judging said review and determine how it fits into our own opinion.
That is the process that should preserve one from being subject to the blowings of whatever winds one comes across. I am not sure what I would recommend to someone who would have trouble not finding himself agreeing with any article found on a given movie. I would not, however, advise avoiding the practice of reading on the subject. It seems to me you can only hone your critical thinking faculties by reading as many divergent opinions about as many different matters as possible. Maybe that is the solution: always finding two views that directly contradict each other and work on comparing them.