I would like to know how you would go about reporting an unfit parent, what consitutes and unfit parent, and how old children must be before they can request to live with the other parent?

Why do you consider your parent to be "unfit?" Is there abuse? If so, the parent should be reported to whatever agency in your state deals with child protective issues. As far as "requesting" to live with the other parent, if there is a custody order in place, it stays until it is changed by the court. The other parent would have to file a motion to have the custody order modified and present compelling evidence for doing so to the judge. Your wishes would be given consideration but would not be the do-all, end-all.