The button (Driving Dymanics Control) that the salesman activated is standard on the 5 Series. It allows you to toggle between COMFORT, NORMAL, SPORT and SPORT +. It controls the response of the engine and transmission.
If you want the the suspension to also be tied into the system, you need to order Dynamic Damping Control. This will firm up the suspension as you move from Comfort up to Sport.
Adaptive drive combines Active Roll Stabilization and Dynamic Damping Control. This system activly counteracts the body role of the car when going through turns, keeping the car flat. A friend of mine just got a 550 with Adaptive Drive and says the Active Roll feature is amazing.
I ordered my 550 with Dynamic Damping Control, but opted against the Adaptive Drive, soley to save money.