To disapprove is to object to something, or frown on it. Your parents, worried about head injuries, might disapprove of your joining the football team.
You can say that you disapprove of violence in movies and video games, or that you disapprove of censorship of any kind. Almost everyone disapproves of things like drunk driving or being cruel to animals. In all of these examples, to disapprove is to believe something is wrong or bad. Originally, in the 15th century, the word meant "disprove," but by the mid-1600s the meaning shifted to "the reverse of approve."