If the game freezes, just click inside it (games can get unresponsive if you click elsewhere on the page).
When traveling by plane, the passengers have to be taken to the airplane by bus. You now have the chance to drive this bus, but you will have to be very careful not to crash it. You also have to be fast, because the airport is running on a tight schedule, so keep your eyes on your timer and damage bar at all times. Your goal is to park in front of the passengers and then take them safely to the airplane so it can take off. Enjoy all eight amazing levels. Have fun!