In a large bowl, dissolve gelatin in boiling water. Cool for 10 minutes. Stir in pie filling and pineapple until blended. Transfer to a 13 x 9 x 2 inch dish. Cover and refrigerate until partially set, about 1 hour.
For topping, in a small mixing bowl, combine the cream cheese, sour cream, sugar and vanilla. Carefully spread over gelatin; sprinkle with walnuts. Cover and refrigerate until firm.