Hello Sarah. You've got a great name! Hollywood Studios is going through quite the transition at the moment as imagineers are working hard to get started on the exciting new additions that were announced at the D23 Expo back in August. Hollywood Studios already has Toy Story Midway Mania, (which I think your children will love), and work has started on an all new
Toy Story Land that will include two all-new Toy Story themed attractions. Along with Toy Story Land, a new
Star Wars themed land will be a part of the Hollywood Studios expansion. As you can see, pixie dust is flying all around the park in preparation of the new experiences, so I think that Hollywood Studios can be done in a half day, especially if you plan on not partaking in the thrill rides.
As I said, I think your children would love Toy Story Midway Mania, I think they might also like the Great Movie Ride and potentially Muppet*Vision 3D. There are actually quite a few shows that your children might be interested in. For The First TIme In Forever : A Frozen Sing-Along Celebration is a must do for any Frozen fan, and Beauty and The Beast - Live on Stage is another great show. Voyage of The Little Mermaid and Disney Junior - Live on Stage! might also be of interest to your children. The great part about so many shows is that you get some time to rest your feet and relax. There are also some great opportunities for character meet and greets with Mike and Sulley, Buzz Lightyear and Woody, Disney Junior pals and many others.
I'm running out of space, but if you need anything else, please don't hesitate to ask. Have a magical Walt Disney World vacation!