You are assigned to a specific bus going back to the airport; you should get that assignment hung on your door morning of the day before check out. If not, stop by the front desk that morning before. Bus time should be about 3 hours before your flight (4 hours for international). You need to be all ready to go, kids and baggage with you, 15 minutes before that time.
You can arrange an earlier bus back to the airport that morning before checkout or sooner; you may not schedule a time closer to your flight. If you miss your bus you are not guaranteed a ride on a later bus.
Waiting to check baggage at the airline check stand does not count as being punctual for DME.
Arriving at your resort from the airport, drop off order will vary depending on how busy things are.