R.T.
You can park for free at Downtown Disney and take the bus to the theme park. You may have to wait a while for the bus, though, and it might make other stops so I don't know if the money you save would be worth chopping time off of your one day in the Magic Kingdom-- plus I'm not sure if you know how to get to DT Disney and where to catch the buses (it's behind the House of Blues/Cirque d'Solel), so it may take time in your day trying to find it. You can also hitch a ride (bus, boat, or monorail) from any Disney owned hotel or resort, but most of them have a guard who will question you when you pull up. If you have breakfast at the restaurant at the hotel you could probably get away with it... but of course breakfast would be more than the $14 you are trying to save!! I say bite the bullet and pay the $14, but that's just my opinion. If you do want to do a character breakfast and splurge, there is one called Chef Mickey's at the Contemporary Resort, and then it's a very short zip over to the Magic Kingdom by monorail. Call ahead and get a reservation.