Sure, watching movies is one of the ways to improve your English, but only ONE of the ways, it shouldn't be seen as the only activity that you do in English. If you really want to see progress you need to involve your productive skills-speaking and writing-since watching something is a mere receptive skill. As to translation, I think it's a habit that a lot of learners acquired at lower levels and later when reaching a higher level, translation actually slows down comprehension and hence your speaking making your brain do a double work. I always recommend my intermediate and higher level students stop using bilingual dictionaries and instead look up new words and phrases in monolingual ones: read the definition and the examples and do NOT translate them, you may also look up images in google that usually helps too. Writing down definitions, examples and making your own sentences with the new words or phrases (again, all WITHOUT any translation) normally works as well. This way you will be getting used to create meanings in English without translating. 

I think it can help us to learning any language by watching movies ,but at first watching with subtitle and write the words and sentences that we don't know and next time with out subtitle.

Hi there. I had a friend who was learning English at school but he used to watch a lot of American TV Shows. He picked up a lot more of the English language than his friends because he expanded his knowledge through the use of media. I think it's a fantastic way to learn however it is just learning through listening. This would be a lot slower than if you were combining it with having lessons or just speaking to people that you know speak English.

I think watching movies is one of the great ways to learn English. However the deal is that we have to practice, use, and actually say whatever it is that we learn through movies. I think that is the key.