Replacing handlebars

from here

Shimano Simplex derailleur/crank, Carbolite 103 frame, Mavic rims h/bars.
I've never owned a road bike before, this one clearly needs a bit of work doing to it, I've got to decide whether to strip it down completely, clean everything, replace bearings etc, or just leave the bits on, check the wheels and replace the chain and start using it.
Decisions decisions..