Make crust: Preheat oven to 325. In food processor, combine crackers, sugar and salt. Process to fine crumbs. With machine running, add butter through feed tube and process til it resembles wet sand. Press crumbs into bottom and up sides of a 9 inch square baking dish. Bake until fragrant and deep golden brown, about 10-15 minute Let cool completely on rack.
Meanwhile, make filling. Place 1/4 c cold water in a small bowl. Sprinkle gelatin on top and let stand 5 minutes. In large bowl, whisk together pumpkin and cream cheese til smooth. In small saucepan, combine evaporated milk, brown sugar, salt and spices. Bring to a simmer over medium heat. Add gelatin mixture and stir til completely dissolved. Pour milk mixture into pumpkin mixture and whisk until completely smooth.
Pour filling into cooled crust and refrigerate until chilled and completely set, about 3 hours (or wrap tightly with plastic wrap and refrigerate up to 2 days). To serve, whip cream with confectioners sugar until soft peaks form. Serve with pie.