The yellow button is fitted if you have front and rear PDC. Pushing this button turns on and off both front and rear parking sensors.
When selecting reverse both front and rear PDC are made active, in a manual car these do not cancel when you take the gearbox out of reverse. You can press the PDC button to cancel the sensors in this situation,
The DSC button allow you to select three options. DSC On, DTC - Traction, or DSC Off (ABD-Sport On)
Drive control function switches between Eco Pro, Comfort, Sport and in some models Sport +. Throttle response, steering feel and susension are changed depending on what options are fitted to the vehicle.