Of the ones listed?
Freddy and or Jason.
Freddy can kill you in your sleep, YOUR SLEEP. You can't escape him and he is a force of nature, he doesn't die.
Jason, like Freddy, is a force of nature. You can defeat Jason but he'll just keep coming back. He is a boogeyman like Freddy but lacks Freddy's dimensional mobility but can teleport (you can't tell me that he can't teleport).
Myers is cool and all but he is still just a man.
Leatherface is just a slow cannibal with a chainsaw.
Chucky never scared me. I guess he could be dangerous if he came at you with a knife and you had nothing...