If you are planning on park hopping, the best way to do it is to park your car in the lot of the park you will be ending your day with. So, if you decide to do AK in the morning, park your car over at Epcot, and take a bus to Animal Kingdom in the morning. You can then take a bus back to Epcot and your call will be there waiting when you are ready to leave at night.
The other solution is to just drive to the parks - go to that park, leave and park at the other park. Whichever you think may be the easiest on you and your family!!