Hi Melissa!
Congratulations on planning your very first vacation to Walt Disney World! I am so glad you're determined not to miss Wishes nighttime spectacular, as the sights and sounds will create a lasting memory for your family.
You'll first want to be sure you have the times of the fireworks for the evening in question. Check out this link for
Magic Kingdom Park hours, providing specific times for character greeting locations and ALL entertainment!
Chef Mickey's is really a great character dining option, as transportation is brisk and easy to and from Magic Kingdom. You can simply walk directly over to Disney's Contemporary Resort, or hop on the monorail. I typically plan character meals to take about 1.5 hours. Personally, if fireworks were at 10:00 p.m., I'd be sure to have concluded our meal no later than 8:30 p.m. You'll be back in the park just before 9:00 with the ability to purchase the "best popcorn on the planet" (according to my 8-year old) and scout out a great viewing spot for a "practically perfect" ending to your magical day.
I'd be happy to answer any other planning question you may have, Melissa.
Thanks for visiting,
Sherri