To each there own with what we believe. I believe in ghosts, reincarnation and afterlife very much, so I never question that spirits can linger after traumatic deaths. The Deborah Stone death (crushed to death in America Sings walls) was a fact, and written about by the LA Times a few days later. Park goers claim to have heard a girls voice at the site saying "be careful" etc. Many stories are floating around about people being in the fifth row on Pirates and feeling an arm or hand behind them with no one there. There is a real human skull inside the ride and it was the last ride Walt ever rode right before his death. Fascinating stuff!
Cast member deaths-
http://afterthemouse.com/article/memoriam
Recent WDW deaths timeline
http://www.orlandosentinel.com/news/breaking-news/orl-deaths-at-walt-disney-world-htmlstory.html