People often ask me if ghosts can hurt you. I've heard reports of that happening before, but it's absolutely not the norm. To be honest? I'm more afraid of the living folks.
Once I was with a ghost group that told a story about a former member who taunted the ghosts at Gettysburg and promptly got shoved by one. I don't know how true that is, but it illustrates a basic common sense thing to me: You've got to have respect for something that can see you, but you can't see them. Hmm...if there's something there, who would have the advantage? You? I think not, so why take your chances.
When we investigated Leap Castle, ranked as #1 Most Haunted in Ireland (and that's saying something), we had some team members from a local Irish group along. While taking pics in the famous Bloody Chapel, one of them said, "Pose sexy for me." If that's not disrespectful, I don't know what is. We were really taken aback by their lack of professionalism. An investigation's not the time to play with the ghosts. Hey, if you don't give a rat's ass about yourself, at least take into consideration the folks who still have to be there when you're gone.