I consider positive books as books to improve our life or share an uplifting story. I enjoy this reading, but when trying to elevate my thinking and mood I certainly abstain from reading Hamlet or Othello and stick with Midsummer Night's Dream or Much Ado About Nothing. Some mainstream movies, such as Scream or Hannibal, will not give you positive thoughts. Possibly, Stars Wars or Phenomenon might. There is a TV network called Wisdom that I like to watch when I visit my folks, who have a satellite broadcast.
Wisdom is all about creating a better life and living more abundantly.
For one week only, keep a negativity journal. Learning how often and in what ways we are being negative is the first step to improving our thinking. Admitting there is a problem is the first step to recovery. When this happens to us we will change when we recognize and replace the negative pattern with a positive one. The way to do this is find something good to say to them.