Hello there Cathy!
I love Mickey's Very Merry Christmas Party! I was able to go last year and had the most wonderful time. I'm hoping to make it back down this December and take the kids with me! There are so many activities, shows, and all around great things during the party but, my favorite has to be, Mickey's Once Upon A Christmastime Parade! The parade typically begins around 8:15pm.
Also remember, that you may enter the park at 4:00pm for the party so if you get there early you can enjoy the park or eat without missing any of the events! I hope this information helps you with your planning and if you have more questions, please ask away, we are always here to help! Have a Magical Time at the Walt Disney World Resort! Thanks so much for asking the Moms Panel!
This is all of the information from last year's Mickey's Very Merry Christmas Party (all are a must do!):
Mickey's Once Upon A Christmastime Parade (last year there were two parades 8:15 & 10:30)
Celebrate The Season Show (last year there were three shows 7:45, 10:05, and 11:20pm)
A Totally Tomorrowland Christmas Show (takes place throughout the night)
Special Meet and greets with Disney Characters (from 7:00pm - 11:30pm)
Character Dance Parties (takes place throughout the night)
Holiday Wishes Fireworks (last year it was at 9:30pm