In a medium bowl, combine the graham cracker crumbs, sugar, and melted butter until well mixed. Press the mixture into the bottom of a 9-inch springform pan. Bake for 10 minutes, then let cool.
In a large bowl, beat the cream cheese and sugar together until smooth. Add the vanilla extract and eggs, one at a time, beating well after each addition.
Stir in the crushed Oreo cookies and heavy cream until well combined.
Pour the cream cheese mixture into the springform pan and smooth the top. Bake for 45-50 minutes or until the cheesecake is set but still slightly jiggly in the center.
Let the cheesecake cool for 30 minutes, then refrigerate for at least 2 hours.
In a medium saucepan, combine the peaches, mango, sugar, water, and lemon juice. Cook over medium heat, stirring occasionally, until the fruit is soft and the liquid has thickened, about 15 minutes.
Serve the cheesecake with the peach and mango topping on top.