I kind of doubt it. Having been to the area you really need a rental car to see other things in the area. As for the Lei greeting, that would most likely be done once you check in. At least that's how it was when we stayed at the Marriott in Ko Olina.
Having said that, if Disney is planning a lot of off site excursions then they might do a bus/lei package from the airport. I think we'll still rent a car as we'll want to explore a lot on our own.