Hi Brad,
Thank you so much for visiting the Disney Parks Moms Panel with your question. We love helping guests to plan magical vacations.
If I had one short day and one long day, I would likely spend the longer day at Epcot and the shorter day at Disney's Hollywood Studios. While both parks are amazing and have so much to do, for me Epcot takes more time as it has both Future World and World Showcase to explore.
Along with this, you should also consider if either theme park has
Extra Magic Hours on one of the days that you are going. Extra Magic Hours allow guests of Walt Disney World resorts to spend extra time before a theme park opens or after it closes on certain days. This is a perk for guests staying at Walt Disney World resort, so this only applies if you are staying at a Walt Disney World resort. I checked this for a week at the end of April this year, and I see that Epcot has Extra Magic Hours on a Tuesday night, and Disney Hollywood Studios has Extra Magic Hours on Friday night. In this case, I would suggest that you go to Epcot on Tuesday and Disney's Hollywood Studios on Friday, as this would give you extra time in each park.
To make your decision, check the calendar for
Walt Disney World theme park hours. You can toggle the date at the top of the screen to check for park hours on your specific travel dates. Please note that Extra Magic Hours can change, so do check for your specific dates.
I hope that these thoughts are helpful for you, Brad. Have a great time planning, and please do let us know if you have any further questions.