The answer to this question is partly very clear and partly a question of listening to your conscience.
The clear part
Let’s begin with the very clear part. Of course as a Christian one should avoid pornography, excessive violence, programs which support occultism or which are filled with cursing and an anti-Christian message. But what if there is some violence in a film and what if there is a love scene in a movie? Or what if there is nothing specifically wrong in a program except that it shows a completely different, non-Christian lifestyle?
Some Christians might say you can’t watch a program like that, others say you can. A helping guideline in this question is given by the apostle Paul. He shows us, that God gave us a conscience which serves us in cases which are less clear in God’s Word. For example in Romans 14 Paul talks about eating meat or keeping a day apart for God. Some Christians in his days said you cannot eat meat, others said you can. Some Christians say you have to have a special day during the week, others say all days are the same. Paul gives two things to consider when we think about less clear questions like this.
The first thing is: Are you harming a brother or a sister who is weaker in faith by doing something that they consider inappropriate for a Christian? If that is the case, we should not watch.
Listening to your conscience
The second consideration is: What does your own conscience say? You “live for the Lord” (Romans 14:8). Can you combine living for the Lord with the things you are doing? In Romans 14:22-23 Paul says: “So whatever you believe about these things keep between yourself and God. Blessed is the one who does not condemn himself by what he approves. But whoever has doubts is condemned if they eat, because their eating is not from faith; and everything that does not come from faith is sin.” So if you are not so sure when you’re watching some program, you already have your answer: don’t!