A taxi cab from John Wayne to the Disneyland Hotel runs about 40 dollars. Uber cars are plentiful at John Wayne and in the Disneyland Resort District, and cost less.
Whichever choice you make, the access to and from John Wayne is super simple and can be very fast. The one exception is the 4pm to 6pm weekday window, when the northbound 55 Costa Mesa Freeway is very congested between the 405 San Diego Freeway and I-5 Santa Ana Freeway, and there's not a good option to avoid the Costa Mesa Freeway to get to Disneyland. It doubles the 20 minute trip time trip during those hours.
Getting into a taxicab at John Wayne is a thing of beauty. The triangle shaped part of the building in this photo is where the taxicabs are in that little open plaza, literally steps from baggage claim, and just a stones throw from the airplane you just flew in on.
You depart your plane, walk a few yards to the escalator down to your baggage claim carousel, then walk past this guy in the triangle shaped atrium. Hello, Mr. Wayne!
Then you walk 20 yards out to the taxi stand where a line of cabs is always waiting, and jump into the first cab and say "Disneyland, please!" . About two minutes later you have exited the airport circulator road and are merging onto the 405 freeway at 70mph. 15 minutes later you can see the Matterhorn through the windshield. You're there!
If you're smart enough to choose John Wayne Airport, you can get from your airplane seat to the check-in desk at the Disneyland Hotel in 45 minutes or less and a 40 dollar cab ride. Tack on an extra 30 minutes if you are renting a car, or waiting for a shuttle bus that may make additional stops.
If you really wanted to save money, nearby South Coast Plaza has a shuttle to Disneyland ($10 adults, kids free) and even if you factor in an Uber to the mall the total would still be less than a $40 cab ride. But that's a lot of effort just to save a few bucks.