Generally, I don't believe in censorship, though there might be necessary exceptions in matters of national security. The danger in such, of course, is that the privilege to censor for "national security" might be abused for political advantage.
I certainly don't believe that people should be ordered by religious authorities to avoid reading material that disagrees with the "party line." If a group of which one is a member tries to restrict his/her access to certain information, that should be a big red flag.
On a private basis, I believe that parents should exercise care as to what their children are reading or viewing. The younger the child, the more discernment should be used as to what material is appropriate. By the time a child reaches the mid-teens or so (the age could vary depending on the intellect and maturity of the child), there should be very little material that the parents would prohibit. I should emphasize that I'm talking here about intellectual material: I would consider pornography a separate issue when dealing with minors.