I have wanted to be an Imagineer since I was about 12, when I saw an ad in Model Railroader magazine saying Disney was looking for artists, architects and model makers. It's always been my dream job... but that doesn't really fit the question, does it?
My favorite position on-property would probably be a VIP tour guide. I saw these guys on a Travel channel show (Disney Royal Treatment, I think). They escort folks around, get them prime seats, order their days to see everything they want.
That, or, to be a chaplain at the Grand Floridian. You spend your days as an integral part of couple's most important day of their life. And with the cost of a Disney wedding, the tip for the chaplain is probably pretty nice. And, every wedding I've ever been to, the preacher was invited to the reception. Open bar, premium food. Sounds good!