1. Preheat oven to 350°. Process first 2 ingredients in a food processor until finely crushed. Firmly press mixture on bottom and up sides of a lightly greased 9-inch springform pan.
2. Bake at 350° for 10 minutes. Cool completely in pan on a wire rack (about 30 minutes).
3. Meanwhile, let vanilla ice cream stand at room temperature 20 minutes or until slightly softened. Stir together raspberry jam and orange juice until smooth.
4. Place ice cream in a large bowl; cut into 3-inch pieces. Gently fold chocolate and 1/2 cup raspberry mixture into ice cream until just blended. Spoon mixture into prepared crust. Drizzle top of ice-cream mixture with remaining raspberry mixture, and gently swirl with a long wooden skewer or knife. Freeze 3 hours or until firm. Let stand at room temperature 15 minutes before serving. Garnish, if desired.