What do blind people see? Well first of all, they can't see black because you need to be able to see to know what black is. Whilst only a small percentage of blind people are completely blind, they are oftentimes still able to see light and dark.
No shapes, no shadows, just the presence or absence of light in a room.
It would probably be just as hard for a blind person to imagine seeing as it is for an able person to imagine being blind.
If I had to choose, sight would be the last sense I'd give up. Sure stuff like hearing, feeling, smelling, and tasting are important, but nothing beats sight.