Hi Caroline!
Thank you for bringing your question to the Disney Parks Moms Panel!
I really enjoy my private time at Walt Disney World. Being able to take my time and do exactly what I want is very special!
I honestly don't think you could see it all in one day, but you could see a whole lot! You should go to Animal Kingdom first since it closes earlier than the Magic Kingdom. Be sure to research the parks and plan out your "must-do" list. Touringplans.com has some great ideas and plans that can help maximize your time, based on how much time you have and what you want to do/see.
If there is a chance you will be back in the next few years, I would recommend focusing your day on the Magic Kingdom. You could really relax and enjoy the park all day long. Animal Kingdom is actually undergoing some major renovations and you will want to get back there to see them in the next couple of years. Be sure to follow the
Disney Parks Blog for updates on Animal Kingdom's progress.
While you are trying to see as much as possible, also don't forget to relax and take it all in. The magic of Disney is truly in the details.
I hope this helps! Please let me know if you have any other questions.