I haven't driven from MCO to port but I have driven from my WDW resort in the past. It's an easy drive.
What company you use to rent a car will depend on how you handle the car situation once you get to port. Will you be leaving it in the garage/lot while you cruise? Or, will you return it to the rental company and rerent when you disembark?
If you return the car, you want to use a company that runs a shuttle to and from the ship. I know
Budget runs many shuttles....they always seem to be at the ship!!
I would run figures to decide which way is better...keeping the car and paying for parking, returning the car and rerenting, or just taking
DCL transfer bus.
Usually? It's cheapest to rent a car, return it while you're on the ship and shuttle back to rerent the car after the cruise. But, I have found that sometimes, it's almost as cheap to keep the car, park it across from the ship, and just hop in and leave after the cruise. It was worth the addlt $25 to keep the car and not have to shuttle back and forth.