Is a dream reality possible?

[R-e-n-n-a-t]

This is possible, and we would never know.

But really? That's the same argument theists use for God. It might be so it must be.
Sorry, that doesn't follow.

While reality isn't much more than a perception (I agree there), you lost my support when you suggested we're in a computer. It's interesting, yes, but I hope that comment was intended to provoke thought rather than actually voice your opinion on whether or not we're in a computer simulation.