They want everyone out of their cabin by 8:00 am and off the ship by the latest 9:30 am so after that time there won't be many buses....may 10 am would be the latest.
It takes just under an hour to get to MCO from the Port The cost is $35 pp
The good news is if you are flying domestic and are on one of the participating airlines you can sign up for Onboard Airline Check In which means
DCL will check you in, deliver your boarding passes to your cabin, deliver your airline luggage tags to your cabin all the night before your cruise. You must sign up for this service but it is complimentary. Again, your flight must fit the parameters of the program.
Also, there are plenty of shops at MCO to keep you busy for awhile.
MJ