To Kill a Mockingbird Chapter 1

Chapter one of To Kill a Mockingbird is very interesting because Scout starts it by explaining her family history. Her, Jem and Dill all have a very close relationship with each other and are all very curious about a character named Boo Radley. They've heard many rumors about this character such as he got in trouble for the law and as a punishment his father imprisoned him in the house and not until 15 years later, he stabbed his father with a pair of scissors. I wonder if these rumors are true or if Boo Radley is actually a decent person. And what is his role in this story?