I fully agree with your point regarding a good movie. It can assist the learning process, particularly because it raises the students' interest in English. In the past, I have often recommended movies to my students, which we then informally talk about outside of class. I also incorporate discussion activities or comment on movies, actors, and current events into my lessons. These are all relatable to the real world, as opposed to fictitious characters from a textbook; this then better highlights vocab or grammar, or generates interest.
My problem, however, comes when a teacher pops in a DVD for a full 90-minute class--this is not teaching! I also personally think it's ineffective to show twenty minutes of the same movie each lesson as an alternative means to get through the whole movie. There are so many better uses for movies, as Charmaine has also pointed out, that also take into consideration the time in the classroom.
I'm not entirely against movies, which maybe my initial post conveys. They are great for self-study, as the student can replay it again and again, working at his/her own pace. If you want to incorporate movies into the class, then snippets are also wonderful. Or you could assign students to watch a movie of their choice, and then give an oral presentation or discussion (or even, a written report, if you so choose). Snippets also lend themselves well to listening practice, rather than a conversation from a tape or CD. The ideas really are limitless.
When EFL students have so little contact with the target language, though, I can't budge from my initial comment. It's best to have them speaking, listening, and thinking--participating, in other words--in English as much as possible in the short time they are in my classroom. Those ninety minutes don't allow an entire movie, I'm afraid.
Lastly, although this is more a personal preference, I like TV programs better. They are written with commercial breaks in mind, so a scene plays out in 5 or 10 minutes. This works well to generate discussion, speculation, or whatever I have planned... while keeping to my time constraints.
On a side note, I hope that my initial post didn't come across as someone who dislikes his job. I love teaching, and love working with students.