Heat oven to 350F. For crust, mix crumbs and butter. Press onto bottom of a 9 inch springform pan. Bake for 5 min.
For filling, beat cream cheese and sugar until smooth. Beat in eggs one at a time. Beat in sour cream and vanilla. Stir in chocolate chips. Pour over crust. Bake for 45 min or until the cheesecake is set. Turn off oven, open slightly and leave cake in oven for 30 min. Remove from oven and let cool completely.
For topping, bring cream to a boil over medium heat. Pour over chopped chocolate, stir until smooth. Pour over top of cake.