ANY airline can be used when arriving. Regardless of who you fly Disney will haul you and your luggage.
For departures, United (and Ted), Delta (and Song) and American were on the list the last time I checked. For those airlines you can check your luggage at the resort and just go on the bus to MCO. For all other airlines, you carry your luggage on the bus (or really it goes under the bus) and check it at the airport.