In a small bowl, mix together Graham Cracker crumbs, melted butter and sugar. Press mixture onto bottom of 9-inch springform pan and bake for 10 minutes. Remove from oven and let cool.
Reduce oven temperature to 300°F.
In a large bowl, beat cream cheese, peanut butter, sugar and vanilla extract until smooth and creamy.
Add eggs, one at a time, beating well after each addition.
Stir in chopped Reese's Peanut Butter Cups with a rubber spatula.
Pour mixture into prepared crust and bake for 55-60 minutes.
Remove from oven and let cool to room temperature. Refrigerate for at least 2 hours before serving.
Meanwhile, to make the topping, combine peaches, mango, sugar and cornstarch in a medium saucepan.
Gradually stir in water and bring mixture to a boil over medium heat. Cook for 2-3 minutes or until mixture thickens, stirring occasionally.
Remove from heat and let cool to room temperature. Spread over cheesecake before serving.