Combine graham cracker crumbs, butter and granulated sugar in medium bowl. Press onto bottom and 1 inch up side of 9-inch springform pan. Bake for 6 to 8 minutes. Do not allow to brown. Remove from oven; cool.
Beat cream cheese, granulated sugar and brown sugar in large mixer bowl until fluffy. Beat in eggs, pumpkin and evaporated milk. Add cornstarch, cinnamon, and nutmeg; beat well. Pour into crust. Bake in preheated 350 degree oven for 55 to 60 minutes or until edge is set.
Combine sour cream, granulated sugar and vanilla in small bowl. Spread over surface of warm cheesecake. Return to 350 degree oven and bake for 5 minutes. Cool on wire rack. Remove side of pan; chill several hours or overnight.