Hi Michelle,
After traveling with a family of 6 you certainly do need a little time to relax and gear up for the vacation ahead. That's really good thinking on your part! Downtown Disney is a great way to spend your first evening. I know it's not fancy, but we always enjoy Earl of Sandwich. Even if the lines are long, it's quick, it's delicious, and it's relatively inexpensive. You can grab a bite to eat and then stroll around Downtown Disney, shopping or just looking. Save room for dessert and grab a treat at Goofy's Candy Co.
If you're looking to do a bit more, why not try Fork & Screen? You can watch a movie at the AMC Downtown Disney, and food will be brought to you as you eat.
Splitsville is another option. It's not your average bowling alley food. You'll be delighted by the selections that are offered. They don't take reservations yet, so it may not be an option, depending on how crowded it is when you go.
If you're looking for a traditional, sit down meal, Raglan Road is a fun option. The nightly entertainment is great, and they often give guests, especially children, a chance to try some Irish dancing.
Hope this helps. Have a magical vacation!