Hi Susan,
First of all, Congratulations on 25 years! A trip to Walt Disney World is a wonderful way to celebrate your special occasion.
You know your son best. As a mother of a 12 year old, I tend to think it's a bit long for a meal. While he might enjoy the food options, it might be too long for him to sit, dressed up, enjoying the ambiance. Then again, every child is different. It is a special treat, and you know your son's personality.
If you think it might be a bit much, how about considering dinner at Jiko or California Grill? Both restaurants offer delicious food in a beautiful setting. The view at California Grill is stunning!
Flying Fish Cafe has a chef's tasting experience - a 5 course meal with wine pairing and the opportunity to interact with the chef. Another fun option might be to
dine with an Imagineer. This experience is available at both Flying Fish Cafe (dinner) and Hollywood Brown Derby (lunch).
Whatever you decide, I'm sure it will be a truly memorable and magical experience.
Hope this helps. Have a magical vacation!