To the OP:
I'm a single male and will soon be 33 and my favorite Disney movie is Sleeping Beauty, so I like to meet Princess Aurora, and on some occasions have met other princesses as well while waiting to see Aurora. She has always been wonderful and never acted like she just wanted to get me out of the way so she could go back to meeting all the little kids waiting to see her.
On one occasion at
Disneyland, she and I had an interesting conversation specifically about her film and a couple days later, the very same CM was portraying Aurora in Disneyland's parade. She happened to look straight at me during the parade and waved right at me.
Most CMs know that people love the Disney movies, so it usually doesn't phase them when adults want to see them too. in my very strong opinion, the only person who can decide that you're too old to meet the characters is you. In all honesty, what difference is there between standing in line to see Mickey Mouse or screaming your lungs out at a rock concert because you love the band playing and getting a glimpse of them far away from you on stage? There's nothing wrong with either one, although some people seem to have a problem with those of us who want to meet Disney characters because they have some special meaning to us. And it's their problem.
That said, keep in mind the following if your an adult who wants to meet characters. It will probably help you feel more at ease and can often make for a more fun meeting the characters.
1. Treat them with respect, especially when you're meeting a female face character. If your daughter or sister was a Disney CM portraying a princess, would you feel comfortable if another male guest treated her the same way you're treating the princess that you're meeting now?
2. Know who the characters are and what their personalities are like. The CMs have spent a lot of time studying the film/cartoons the character appears in so that they can become the character, right down to the physical mannerisms and speech patterns of their movie counterpart. I believe they really enjoy getting to play the part on stage with an adult who appreciates how well they portray the character.
On one occasion I got to spend 3 minutes or so with Sully from Monsters, Inc. simply because I told him that I visited Pixar once. He literally followed me around, and insisted that I be first in line to get my picture taken with him. He even took some special scaring pictures with me that he did not do for the little kids in line behind me. It all happened because I showed the CM inside the costume that I knew and appreciated Pixar's work.
3. Going along with #2, don't be afraid to have fun with the characters. When you know who they are, you can really have some fun. Give Chip and Dale peanuts, or ask them if they've tormented Donald Duck lately. Drop to one knee and kiss the hand of Minnie or Daisy(do
not do this with a female face character). Ask Mary Poppins how to say her supercalifragilstic... word backwards.
If you meet a princess, ask her a question that shows you know her movie. I've heard people say you should ask Ariel what human treasures she's found lately. Ask Belle about what books she's read recently and so on and so forth. Tell Jasmine that you think tigers are cool. If you can't come up with anything or freeze, then just give her your best princely bow and be polite.
In my experience, when you show a character(be they face or fur) that you know who they are, then you're much more likely to have a great memory and maybe a fun story from your time in Disney to go along with the photograph of your time spent meeting the characters.