I have now been to all of the character meals. Three of them I've been to with DS (who is almost 14). I will say, we've had the buffer of his little sister at all of them, but he seems to enjoy himself as well. Of them all, I think Minnie's was the most interaction by him, as he got a picture with Pooh (his very favorite character) and Max and Hook. What we have done is seat the boys on the inside at character meals, letting DD get most of the interaction.
That all being said, I guess it would be a question of whether you're wanting to do a character meal because you want to (and basically hoping she won't ruin it)? because you think she will secretly enjoy it? because you think you will both love the food? If you want to go and you're hoping she will tolerate it, then I'd say go ahead, and pick one with food you think she'd like. If it's more that she is secretly wanting to go to one, I'd have to say I doubt it. I've loved the food at all the breakfasts I've gone to. Others not so much.
If you're looking for something that will capture her attention and that she'll really love, I'd say do something special and more grown up that you maybe wouldn't do when the younger kids are with. Focus on a type of food you think she'd really like or a type of restaurant she'd really like. Maybe the atmosphere of Blue Bayou (though I like lunch better than dinner.) If you think you'd both enjoy it, go to ESPN Zone and play games and eat there. If you think she'd love to get dressed up and go to a nice restaurant, do that. If you think she'd love to eat pasta and watch the electrical parade, do that. Something that shows that you recognize she's moved into a different age than her younger siblings. Personally, I always loved the characters and would have enjoyed having a meal and having pictures with them at any time. But, one of my most memorable teen-aged family experiences was when my mom surprised me, took me shopping to get a "nice" dress and then she and I went out alone for a white linen table cloth steak dinner.
One of the things that I loved on the Ladies only trip was eating at places I wouldn't usually eat, either because I didn't think everyone would like it or it was too expensive for everyone to go to.
Have a great time while you're there. Sounds like a lot of fun!