Well, I am blind and I can assure you that I have dreams where I can 'see' everything!
"Thoughts that include vision"? Why? Do you visualize everything you 'think'? I know that I did not when I could see and I do not do so now!
I do not see black; it is more like a milky whiteness.
You DO realize that there are different kinds and levels of blindness, right? We are not all the same, we were not all born blind and we all have different experiences.
I answered your questions because I believe in educating others and satisfying their curiosity but please realize that there are many people who will find your questions insulting and infantile.