My son actually loves princesses almost as much as he likes his power rangers and whatnot, so I'd let him go there - and I think under 3 gets to eat free. But, if he would be a distraction for the others, or it is a girl thing only, you could ride the monorail around, which most kids love to do. I am not sure what time chef mickeys is open, as I have only been there for breakfast, but they have characters, too, and toonland in MK is usually a very fun place for the little kid set. (at least for mine) they can look at mickey and minnie's houses, and stand in line to meet and greet charachters, then run around in the playground there.
My almost 3 year old loved breakfast at the crystal palace cause he got to see pooh and tigger et al, but he couldn't last the whole time.
Have fun !
I believe the princess Tea party the OP is referring to is the one that is $200 plus. It is for girls. It isn't a regular charater meal. Here's the info from Deb's site:
Grand Floridian's Garden View Lounge
The My Disney Girl's Perfectly Princess Tea Party at Disney's Grand Floridian Resort and Spa has become permanent.
Your little girl can dress up and have a special tea party with Princess Aurora from Sleeping Beauty. The tea party is hosted by "Rose Petal" a magical rose from Aurora's garden, who will lead sing-alongs, storytelling and a princess parade.
In addition to the tea party, princess cake and meet and great with Aurora, each guest from 3-11 will receive "My Disney Girl" collectable doll plus accessories; a tiara, Princess link bracelet, princess scrapbook page and a "Best Friend" certificate.
If a little boy wishes to attend, they will receive a teddy bear and princely crown instead of the doll and tiara!
Adults receive a selection of hot tea and a luncheon plate with small sandwiches, cheese briquettes, lavosh crackers and fruit.
Children receive juice and a luncheon plate with fruit, small sandwiches and heart-shaped peanut butter and jelly sandwiches.
$225 includes gratuity (but not tax) for one adult and one child ages 3-11. Additional adult guest (12 and older) is $75 plus tax and an additional child is $150 plus tax. Refunds available if you cancel more than 72 hours from the date of your event.
Book up to 180 days in advance. Your credit card will be charged by WDW prior to the event.
Sunday, Monday, Wednesday, Thursday & Friday 10:30am - Noon. Arrive 15 minutes prior to check-in.
Like others said you can go to Chef Mickey's for a character meal. Also, you can grab some food to go at Gasparilla Grill at the GF, then take it on a boat at the Marina at there. Your DS might think it's cool to be on a boat and you can cruise around the lake and see the castle. You can also ride the monrail, then stop for breakfast at any of the resorts on the loop.