How do I access the hidden options menu in my Audi A2?

I've heard that there are some secret options available in the Audi A2, such as enabling the hidden service mode or resetting the oil change interval. How can I access this menu and what options are available within it?

To access the secret options menu, hold down the MENU and CAR buttons simultaneously for 10 seconds while the car is in park. This will bring up the hidden menu where you can access various settings and functions.