We always rent a car and drive ourselves. It takes one hour. Some folks do one way rentals. You can drop off the car and they will shuttle you to your port.
There are several companies that have a shared shuttle service from MCO to Port Canaveral, prices are in the $40-$50 per person round trip range (plus 20% gratuity). This would be $80-$100 + 20% gratuity ($110-120) for you and you signifigant other. This would also mean finding your way back out to the airport (additional cost). Some shuttles offer group pickups at/near resorts for additional costs.
The other option would be a car service such as Mears. I believe their cost is $170 each way plus gratuity (for up to 4 passengers) but they will pick up directly from your resort $340 + tip ($400ish)
When you see the cost of the other option, the car rental really is the best option ($100 + $10 gas + $6 tolls)