I am assuming that you have already reserved DME with whomever you have booked your vacation stay with. Terrific. So...about a month prior to your departure, you will get a packet from DME. This will include travel vouchers for each person on the room reservation. You have to have that voucher to get on the bus. You will also get one yellow luggage tag for each person. This will go on your checked luggage. If you need more than that one tag pp, you can call DME and have them send addtl tags.
When you are getting packed, at home, just put those yellow luggage tags on your checked bags. Be sure to keep out the info packet, with vouchers, in your carryon bags!! When you get to your departure airport, say goodbye to your checked bags!! The next time you see them will be in your WDW resort room!!
Okay...so now you arrive at MCO....head down to level 1, Side B of the airport. You will see the DME checkin area at the end of that area. You will be directed to the appropriate bus line. The average time, from gate to resort, is about 70 mins.
You can expect your bags, in your room, up to three hours after resort checkin. It is always a good idea to pack anything you may need for the first day of your trip in your carryon bags...airlines do misdirect luggage, so it's good to have what you need, just in case.
Now...here's the catch. If your flight arrives between 10pm and 7am, your tagged bags will not be taken from MCO to your resort. DME discontinues baggage delivery at 10pm. The buses still run...they are a 24/7 service.
My recommendation is that anytime you arrive close to 10pm (actually from 9pm on), leave the tags off and get them yourself and bring them to the bus with you. Otherwise you will be up fairly late waiting for them to arrive in your room.
Hope this helps..any questions, just ask.