Things we have done?reactions we got
At Chef Mickeys:
one son wore a goofy hat (green striped one with the ears) other in Mickey Mouse ears. Goofy stole my oldest's goofy hat and had my son chase him down. Donald got VERY upset about the mickey mouse ears and stomped off. When Mickey came around, all three guys left me sitting there alone (hubby and two boys) so Mickey decided to have dinner with me (great pick!)
Mary Poppins: the boys sang supercalifragilisticexpialidocious to her (that was a riot) and we got a classic Mary Poppins line from it
Alice: DH bowed and complimented her on her dress and she began a discussion of gallant gentlemen
Belle (yellow dress): I asked her who her modiste was and where I could get a version of her dress (and I got referred to some magic dinnerware)
Lilo and Stitch: my youngest showed up with a stitch stuffed animal and my dh in a stitch hat. Stitch kept coming up to us while waiting in line (at AK) and hugging the stitch animal. They then got really excited when it was our turn to come up to them and made a big deal about Stitch now having brothers! He then signed both the stuffed stitch and the hat. (my dh also got LOTS of comments walking around the parks with his stitch hat on, especially from kids screaming ITS STITCH).
Donald Duck: sign the Mickey Mouse Club song to him, also you will get a great reaction if you tell him he's your favorite over that Mouse.
Tigger: ask him to go bouncing with you
The Up characters (not sure if there are still there). We had great interaction with them, especially Karl as I tried to get him to trade my his Grape Soda Pin for one of my pins
If I remember correctly I think we asked the Beast about Roses, this was after he showed up right as it was our turn and my sons were talking to Belle and Beast tried remove the competition for Belle
If your on the ropes during the MK parade, the Wicked Step Sisters flirt with all the men and there was lots of interaction from ladies hiding their Dh/Boyfriends from them and watching the step sisters pout