Research on opening of movies, Genre: horror!

Paranormal Activity 1

At the beginning of this movie it starts with a normal day, just a normal life and normal events happening, i think this is to introduce the characters and setting before confusing the audience with lots of events all happenng at once.
It starts off with just mild horror experiences and then it gets worse and worse. They do this to keep the tension going throughout instead of giving away all the main events and then ending the film really calm.

Wrong Turn 2

Wrong turn starts with someone in a car driving perfectly fine through a forest, this has the least amount of tension. Then they introduce a kill, this is tell the audience bad things are going to happen, they then go back to normal life where a tv channel are filming a new tv show in the forest. We know now though that the forest is dangerous which opens to us expecting more...