To answer the question about ghosts... I don't know if I believe in the dead, but I definitely believe in astral projection and that many who try it are... clumsy.

I used to get dream, nightmares. A spider coming down over my head. One night, visiting friends, I had the nightmare, awoke with a yell. The next morning, the mrs. commented on it. The mr. said it was his fault, he was trying to visit me and I rejected the visit. I explained the nightmare and he said it was because I didn't recognize the visit for what it was.

Now the reason I believe it... I've had more such visits but instead of being nightmarish, I just tell the clumsy dumbasses to go away. And they do.