Hm. The concept of a scary story around a campfire is a decent start, and I understand the payoff at the end. I can't think of anything in this script that really went well, though.

Characters should have names. I know you're telling the story like a legend, your characters should have names at least for readers to refer to.

The characters themselves were undeveloped. They existed solely for the story and that's it. Milkman enters, kills one, kills another, kills another, end of story. There was no character built with him. His insanity might justify one death...barely...but his wife and then daughter? We need more to go on to buy that.

The dialogue was too blunt. The characters state exactly what they need and feel to as if they are narrating the story preceeding each line with "And I said something like..." It needs to be a lot more subtle here, almost dancing around the subject unless absolutely necessary to say it.

The outer story is rather thin as well. Sure, how much can you say about the storyteller and his listeners? But the rustle and here comes the Milk Man? Just didn't work so well after the tale. Need to spend a little time with these people to even care. Might be better to leave them out of it.

I'm sure it's been beaten into the ground, but fully centered is way off on format. Go here: http://www.simplyscripts.com/WR_format.html for tips on formatting.

Every script can be rewritten to be at least good, and this one can be as well. It will take a lot to do it, but if you want to improve your writing, there's no time like the present to work on the all important skill of rewriting.