Hi Ramona,
I'm so excited for you to experience your very first visit to the Walt Disney World Resort! You are going to have a BLAST!
It's fantastic that you've already purchased tickets to Mickey's Not So Scary Halloween Party, as that's definitely something I'd recommend doing during a September or October vacation. As for your other seven days, I'd recommend planning at least one more full day at Magic Kingdom Park, and possibly even two more days. My family loves beginning and ending our vacation there! You'll be able to meet beloved Characters, enjoy the attractions, and immerse yourselves in the stories and magic. At Epcot, you'll be able to experience all of the usual fun, but with the
2018 Epcot International Food & Wine Festival going on, there will be new foods to try (including some kid friendly options!), concerts, and some special activities that your whole family will love! There's enough to do that I'd suggest spending two days at Epcot. The all new
Toy Story Land will be open at Disney's Hollywood Studios, and you definitely won't want to miss feeling like a toy in Andy's backyard! Disney's Animal Kingdom is always a blast, too, with lots of attractions, shows, and animal encounters. I'd suggest at least one full day at each of those two theme parks.
That leaves one day left. If I were you, I'd plan my last day of vacation at Magic Kingdom Park and leave my next-to-last day open to revisit your family's favorite theme park. You can go ahead and make FastPass+ selections ahead of time, but feel free to change plans and go with the flow to experience your favorites again! I hope you and your family have a truly magical vacation, Ramona!
Missy