Black And White Chesscake

1 1/2 cups graham cracker crumbs
1/4 cup granulated sugar
3 tablespoons cocoa powder
1/2 cup butter, melted
3 (8-ounce) packages cream cheese
1 cup plus 2 tablespoons granulated sugar
2 tablespoons all-purpose flour
1 teaspoon grated lemon peel
1 teaspoon grated orange peel
3 large eggs
2 large egg yolks
1/2 teaspoon vanilla extract
1 (6-ounce) package or 1 cup semi-sweet chocolate, melted
3 tablespoons whipping cream