How do blind people dream.... hm... I can only guess, but the only thing that would make sense, is that they perceive their dream world exactly the way they perceive their waking world. So in case they've been blind their whole life, they won't see any images, but touching, smelling, hearing etc. will be just as or even more vivid than during the day.

It would be interesting to find out though if it makes a difference when they were able to see during a certain period of their lives, usually childhood, and turned blind afterwards. Do they see images in their dreams which they would never be able to see while awake because their brain still has the memory of it??

That's a very interesting issue, I guess...