In a large bowl, combine the crumbs, sugar and cinnamon; stir in butter. Press into an ungreased 13 x 9 x 2 inch baking dish.
In a large mixing bowl, beat cream cheese until smooth. Beat in sugar and eggs until fluffy. Pour over crust. Bake at 350°F for 15-20 minutes or until set. Cool on a wire rack.
In a large saucepan, combine the pumpkin, egg yolks, 1/2 cup sugar, milk, cinnamon and salt. Cook and stir over low heat for 10-12 minutes or until mixture is thickened and reaches 160°F Remove from the heat.
In a small saucepan, sprinkle gelatin over cold water; let stand for 1 minute. Heat over low heat, stirring until gelatin is completely dissolved. Stir into pumpkin mixture; cool.
In a large heavy saucepan, combine egg whites and remaining sugar. With a portable mixer, beat on low speed for 1 minute. Continue beating over low heat until mixture reaches 160F, about 12 minutes.
Remove from the heat; beat until stiff glossy peaks form and sugar is dissolved. Fold into pumpkin mixture. Pour over cream cheese layer. Cover and refrigerate for at least 4 hours or until set.
Just before serving, in a large mixing bowl, beat cream until it begins to thicken. Add sugar and vanilla; beat until stiff peaks form. Spread over pumpkin layer.