Preheat oven to 350 degrees. Butter a 10-inch springform pan. In a bowl, combine cracker crumbs, 2 tablespoons sugar, and melted butter; press into bottom of pan. Bake until firm, about 10 minutes. Let cool completely on a wire rack. Reduce oven to 325 degrees.
Bring a kettle of water to a boil. Beat cream cheese and sour cream on medium speed until smooth. Beat in 3/4 cup sugar, spices, and salt. Add eggs and beat until smooth.
Wrap bottom half of prepared springform pan in foil. Pour in filling and place in a roasting pan. Pour in boiling water until it's halfway up springform pan. Bake until cake is just set in center, 35 to 40 minutes. Transfer springform pan to wire rack to cool completely. Refrigerate until firm, at least 1 hour and up to 1 day.
Sprinkle gelatin over 1/4 cup water; let soften 1 minute. In a small saucepan over medium heat, combine remaining 1/3 cup sugar, lemon juice, and 1 cup water; cook, stirring, until sugar is dissolved. Remove from heat; stir in gelatin until dissolved.
Arrange citrus segments over cake. Gently pour gelatin mixture on top. Refrigerate overnight.
To serve, unmold cheesecake onto a platter. Cut into slices with a serrated knife, using a sawing motion to cut segments; wipe knife between cuts.