It depends on how many people you have.
For the first part you have two options:
You will most likely be cheapest to do a one way car rental. Several companies will allow you to pick up at MCO and return at Canaveral for no extra charge. We like using
Budget. They seem to have the best deals on one way rentals. You would then return the car the next morning before the cruise and either take a shuttle from the car rental agency to the port, or you can take a taxi if you do not feel like waiting.
A private towncar rental is another good option. The company we like to use, Tiffany Towncar, is $109 from MCO to port (for a Towncar which holds up to four passengers). I am sure they could drop you at the hotel as well. This would probably cost you a bit more. but be more relaxing.
For the leg between port and WDW you have three options:
Again, the cheapest option would be a one way rental car. You would be best to go with
Alamo/National which has an onsight return location at WDW.
Again you could go with a towncar. This would probably be the fastest and easiest. Cost varies, but the company I like would be $135 for this trip (it is further to WDW than the airport so costs are higher that way).
Your third option would be to book the Disney transfers for this portion. These will cost $35 per person for the one way trip.
DCL busses do not go to all hotels, you do not say where you are staying.
For the third leg
Assuming you are staying onsight, I think the best bet is to use Magical Express. It is free, and runs quite well. Additionally, if you are flying with an airline which allows it, you will be able to check in for your flight and check you luggage at the hotel.