Speaking of stuff that hasn't been released, I'm still peeved that Disney will never release Song of the South, a charming film from my childhood that has some of my favorite Disney songs. I don't even think the film is racist. By this point they've made it obvious that they consider it an embarrassment (In spite of being the basis of one of their most popular theme park attractions).
I've seen the suggestion among critics and film historians that Disney should release Song of the South
at a collector's price (say, around $50) rather than at a consumer's price (around $20). If Disney took the bullet and moved on, the backlash they fear would blow over.