Walls and Ceilings - If I redo the walls?.........

I am knocking out my plaster in most of my rooms as it is shot, poorly insulated, the wiring is bad and many other things. In my on bedroom the ceiling has this really cool swirl effect that was done around the light fixture with the plaster and it is in good shape. Its a circle around the fixture with swirls in it and it's aprox 4 ft in diameter. Now, I really kinda like the design up their it gives the room some personality so I don't want to ruin it. If I knock out the plaster in the walls, do I have to remove the ceiling plaster as well? I doubt that I could reproduce the design.

Even if you have to patch some of it, the ceiling plaster can stay. Use a good primer (Kilz, etc.) and the different surfaces will both take paint evenly.