1994 Toyota Tarago Suspension

Hi my van jumps around a lot when going over bumps & makes a few noises with it. Is it best to replace the whole strut, springs and mount? The black rubbers are worn. Also I was told that I need to replace four nuts under the car I'm sure he used the word donuts what actual part is that? The noise from that I'm assuming would b a rattle whilst in idle as the exhaust has been replaced.