Hi Bobbie,
Your first visit to Walt Disney World is coming up so soon - how exciting!
I do think that there is enough to do at
Disney's Animal Kingdom to spend the better part of a day there; however, if your time constraint is such that you need to choose one theme park to spend a little less time at, then Disney's Animal Kingdom is probably a good choice. I would suggest thought that you consider your specific child - if you have a child who is very enamored by animals, you might want to consider spending a full day at Disney's Animal Kingdom. If not, you can hit some of the highlights, though of course not the whole park, in a few hours.
If you are going to spend just a few hours at Disney's Animal Kingdom, here are a few attractions that I suggest. Be sure to go on Kilimanjaro Safaris, where you will be able to see exotic animals nearby as you ride through a savannah in a safari vehicle. Be sure to look for the baby giraffe, who has been making some appearances on the savannah! I also suggest that you try to see either Finding Nemo - The Musical or Festival of the Lion King. Both of these shows are amazing and high energy. Finally, you little one might enjoy a ride on the Wildlife Express Train out to Rafiki's Planet Watch. There, you can pet rare animals in Affection Section.
I hope that these thoughts are helpful for you as you plan for your trip, Bobbie! Please do not hesitate to ask if you have any further questions.