Hi Kate!
I think I understand what you are trying to do. You have two days to visit the parks but only have a one day Magic Your Way with Park Hopper Ticket and a Mickey's Very Merry Christmas Party ticket? You also have a reservation at Akershus in Epcot at 1:20 pm. I think I have that right...
OK, if you are mostly interested in going to Disney's Animal Kingdom and Magic Kingdom, you will need to go to Animal Kingdom as early as possible. I'm not sure if you will be there on the 28th but they have an Extra Magic Hour morning that day so that gives you an hour more to explore the park. Leaving for Epcot will cost you a good amount of time and I'm not sure if you are planning to return to Animal Kingdom after lunch since it would be around three to three thirty when you finish eating then have to travel back to Animal Kingdom? My advice if you want to kick off your Holidays with something really fantastic, would be to stay at Epcot and wait for the
Holidays Around The World – Candlelight Processional at the American Gardens Theatre (5:00 p.m., 6:45 p.m., 8:15 p.m.)!
As for Magic Kingdom, I would just wait until the party and get there when they allow you to enter at 4:00pm. I know that the party starts at seven but you can enter the park earlier and take care of some of the non-party activities! Big hint, as soon as you walk into Town Square, check to see what the wait time is to see Mickey and Minnie in the Town Square theater. When I was there early in October, the wait was five minutes around that time!
Thanks so much for asking the Moms Panel! I hope this information helps you with your planning and if you have more questions, please ask away, we are always here to help! Have a Magical Time at the Walt Disney World Resort!