We are painting our cabinets as we speak. The color is white. White makes your room look bigger and brighter...............
We have lived on ny boat for approx. 25 years. Every so often, I would sell what i had and get a slightly bigger one. You are 100% correct about making a space look larger. Every boat I ever had, I removed the counter-tops and table tops and replaced with White Formica. It's amazing how much bigger and cleaner it felt. Attached is a Before/After photos to give an example of 'white'
As for the finish, if the cabinets were made in the 1960's, they are mpore than likely finished with lacquer. Shellac fell out of favor over 50 years before that,
Before you do any sanding on the cabs, wash them down thoroughly with soap and water to remove any grease and oil residue on them. Sanding will only drive the cantamination further into the wood. Wash and rinse several times.
Those cabinets look pretty shot. you will probably never get them to match by sanding and clear coating.
If you know anyone with an HVLP sprayer, there wont be much to mask off. if you dont, this is a good time to buy a self contained unit for around $350. Once you spray, you will never go back to a brush. And, lacquer can be mixed in the store for any color of the rainbow.