So far, I've had only 2 lucid dreams that I could hold longer than a few seconds before waking up. Both were unbelievably real; all of my surroundings were exactly like the real thing, with one exception. I had a vague feeling that was I could see and hear and smell and feel was veiling my from something else, like there was another world just beyond my grasp... which in some ways was true.

As for ghosts: nope.