Although all three are blanket terms but ghosts predominantly used for souls of the deceased wandering the earth, and demons are well... demons, and spirits is more general of the three that incorporates ghosts demons and familiars and many other entities. If by ghosts you mean souls of the departed then there is a bit of a problem:
And beside all this, between us and you there is a great gulf fixed: so that they which would pass from hence to you cannot; neither can they pass to us, that would come from thence. (Luke 16:26; KJV)
In that sense the belief in ghosts (as wandering souls of the departed) seems to go against the teachings of christianity.
Modern day christians do not seem to realize that. The belief about ghosts was only later incorporated into christianity. As you are more religiously inclined and quote bible very often so I thought I should comment on that although I realize now that it was derived more from your personal experience. (Didn't mean to derail this topic. )
Anyway, it is your personal belief, I have no say in that. If you find anything concrete in christianity about ghosts please do share with me. So far I haven't found any. There are some very vague implications but I don't consider them proof enough.
Please read this:
Also the "ghosts" that I have experienced all turned out to be demons. And with time I discovered ways to expose them.
"Spirit" being more general takes away the focus from "ghost". So for a christian it is more appropriate to say spirit or demon imho.
Alright, derailed it far enough. Silly semantics. Back on topic LOL.
As for your experience, I have something to say about it but I think it would be more appropriate to discuss that through PM. Message me if you wish to discuss with me on that.