The two we enjoyed the most (neither with princesses as we have boys.....) were Goofy's Kitchen(breakfast) and Captain Mickey's at Ariel's Grotto(lunch). The food and service at Goofy's was MUCH better, and there was plenty of character interaction (we got there right at opening time). Captian Mckey's had wonderful games with the kids - my Niece said it "Was the best restaurant she had ever been to...." she had chicken strips..... obviously she wasn't talking about the food! We ate outside, the characters had a blast with the kids doing the limbo, conga line, etc out under the gazeebo area.
The service there really was slow, the menu limited and the food was so-so. But the kids LOVED it - more so that Goofys. At Goofys we were seated right away, but even with a PS at Ariel's (and this was not a busy time of the year) we waited 45 minutes to be seated.... the whole meal took 2 hours.
Anyway- Everyone's experience varies, though - I'm sure mine was different than most! We still had a great time and we'll still do it again!