The best episode to look at for holodeck addiction (and general... delusions of grandeur) is a TNG one, here. By the time you actually see him in Voyager, he's... way more well-adjusted, heh.
Not sure how it was handled in DS9, since I haven't seen that one, unfortunately.
Re: That is actually a good question.
Not sure how it was handled in DS9, since I haven't seen that one, unfortunately.