Think of a bus or van shuttle that takes you from the airport to your hotel (or a variety of hotels) and back to the airport. But more convenient because it has its own platform so you don't need to figure out what shuttle is going to what hotel and guess where along a long shared platform it will stop for you. Or if you have ever used Magical Express, Mears' is similar.
You can either make a Mears Connect reservation online or over the phone, or upon arrival at MCO report to their station (terminal B lowest level away from the Hyatt hotel) to get a ride to Disney (Disney's resorts and a few nearby such as the Swan).
Returning to the airport a reservation for Mears Connect is requird and the shuttle will typically be leaving your resort 3 to 3-1/2 hours before your flight. (a little sooner for international flights) Normal deadline to reserve is a day in advance.
Yes, trips are made in the wee hours (to Disney) and booked for the wee hours (homebound) if needed to meet flights.
Is there a better option for two? Short answer, no. Otherwise would require a page full of text, containing several sentences beginning with the word "if", and that I don't have the time to compose and type now.