Automatic Transmission Park/neutral Start Switch problems of the 2000 Audi A4

2001 Audi A4 began to smoke. Drove 5 minutes to a friend's house and parked in driveway, consumer went inside of house, and car was sitting for 20 minutes. Then, someone knocked, and told consumer that car was sitting in the middle of traffic. Car disengaged on its own, and almost ran over two children. Took to dealer, and they said back brake pads, and rotors were burned to a crisp. No conclusion to why this happened or why car rolled into traffic on its own. Also, the brake pedal went to the floor when the consumer applied the brakes. The consumer's investigation showed that there were numerous reports about spongy brakes regarding this vehicle. The consumer feels unsafe driving this vehicke but the dealer and the manufacturer could not find solution to the problem.