Magical Express should get you from ship to Pop Century with no problem. Make sure to get park hopper tickets, that will allow you to go to multiple parks per day. Yes, doing one park in AM and another in PM is a good choice, particularly when doing DHS and Animal Kingdom. I believe that doing Animal Kingdom in the morning with Hollywood Studios in the afternoon is a great way to spend one day. I've been going for over 20 years (more than 60 visits) and have found each of these parks to be 1/2 day parks at best. This will give you one more day to spend at either Epcot or Magic Kingdom where there is a lot more to see and do. Bus transportation is great, it will get you wherever you need to go with Disney, figure about 1/2 hour from hotel to whatever park your going to.