Well, one of the best fellow Imagineers I had the pleasure of working with had no college degree, started as a ride operator in the parks, and worked her way up to executive producer. I don't know if such a career path is even possible anymore, though, and as a previous poster said, getting a degree is really, REALLY important to advancement at Disney and anywhere else, to be honest. It may seem like "just book learning", but part of it is showing employers that you can dedicate yourself to a 4-year task and then achieve it. Having a relevant degree is even better, but many job postings just state "college graduate--mandatory" and that's it.