I know where all the major airlines hub, so to get you to MCO from PHX, the first choice I'm sure of
DCL would be to go with a carrier that hubs there. The next would be one who does non-stops PHX-MCO but does not hub in either city. That is too hard to figure. Then I went with the ones who have the most direct flight going through a hub city.
USAir/America West hubs in PHX.
Delta hubs in Atlanta, Cincy and Salt Lake City with a mini-hub in LAX.
Contental (which code shares with NWA) hubs in Houston, Cleveland, Denver and Newark. NWA is in Minneapolis, Detroit and Memphis (however Memphis is limited on the number of flights, so I don't think that would work).
I don't think DCL will go with Southwest. I don't think they'd do AirTran either.
American hubs in Dallas (besided Chicago and St. Louis), so that may be an option.
The key would be to find out who DCL has set up in their terminal for the baggage check. I will bet you are on one of those airlines. I can't remember who is all there.