Lists by horror2
The authenticity of some of the cases in these movies are open for interpretation. I strongly encourage you to research the real life stories of these movies because the stories are very interesting and in some cases, more fascinating than the movies themselves.
Music has a way of contributing to the atmosphere of films and if done right, can make films seem more terrifying than they would be without the music. Here are the films I feel used the musical score the best to contribute to their overall mood and have memorable scores that become ingrained in the viewer's memory days after the film is over.
These titles do a great job at making the films sound appealing to me.