For the Crust:

1. Preheat the oven to 350°F (175°C). Grease a 9-inch springform pan or a round cake pan.

2. In a medium bowl, mix the graham cracker crumbs and sugar together. Add the melted butter and stir until the mixture is fully combined and resembles wet sand.

3. Press the graham cracker mixture evenly into the bottom of the prepared pan, using the back of a spoon to pack it tightly.

4. Bake for 8-10 minutes, or until the crust is golden brown. Remove from the oven and allow to cool completely.

For the Cheesecake Filling:

1. In a large bowl, beat the softened cream cheese and sugar together using an electric mixer until smooth and creamy.

2. Add the eggs, one at a time, mixing well after each addition.

3. Stir in the vanilla extract, sour cream, and lemon juice until the mixture is well combined.

4. Pour the cheesecake filling over the cooled crust and smooth the top with a spatula.

5. Bake for 45-50 minutes, or until the cheesecake is set around the edges but still slightly jiggly in the center. Turn off the oven and let the cheesecake cool in the oven with the door slightly ajar for 1 hour.

6. Remove from the oven and let the cheesecake cool to room temperature, then refrigerate for at least 4 hours or overnight to fully set.

For the Topping:

1. Arrange the fresh strawberries, blueberries, raspberries, and peach slices evenly over the top of the chilled cheesecake.

2. If using, heat the apricot jam in a small saucepan over low heat until it becomes liquid. Brush the warm jam over the fruit topping to give it a glossy finish.