Line a standard sized 12-cup muffin pan with paper liners and put a gingersnap cookie in each cup.
Stir the gelatin into the warm water in a microwave-safe bowl until nearly all dissolved; let stand 5 minutes.
Meanwhile, in a large bowl, using an electric hand mixer, lightly beat cream cheese first to soften. Then add confectioners' sugar, pumpkin puree, pie spice, and vanilla in a large bowl and beat together.
Microwave gelatin in 10-second intervals until melted and completely dissolved and quickly add to the mixture and beat until well incorporated. This will ensure you don't have gelatin chunks. Then add heavy cream and beat until mixture is fluffy.
Spread or scoop in the muffin cups over the gingersnaps. Lightly spread and smooth the tops of the mixture evenly with a butter knife. Refrigerate until set, at least 2 hours or more.
Remove the cheesecakes from the muffin tins. Remove the liners and top with whipped cream and crushed gingersnaps only when ready to serve, or whipped cream can melt