When you go to work at Disney, your most important job is to keep the illusion of Disney alive. There were always seven or eight of us walking around the park at one time in Mickey Mouse costumes, but when people would ask, "How many Mickeys are there here?", the answer was always, "One." And for whatever time those guests are in the park, they really believe it. It's like a daylong suspension of disbelief.
And what were all the costumed characters that I played, you ask? Well, at Disney, it is prohibited for cast members to say they "played" certain characters, because the characters are "real." Cast members can, however, tell someone they "hung out with" characters. So, to answer your question, some of the more popular characters I "hung out with" included: Mickey Mouse, Minnie Mouse, Donald Duck, Lilo, and Stitch.