Solid Hardwood, Engineered and Laminate Flooring - Refinish an old floor or start over??

My house was built in 1952 and has Red Oak floors throughout the original structure. I am about to remodel my kitchen which includes an addition without hardwood floors. I'll get to that later.

The hardwoods in the kitchen have been covered up with 2 layers of linoleum, followed by 1/4" plywood with stick on tiles on top. We wanted to pull all of this up and refinish the oak. The wood is black, but I figure it will sand out. WHat concerns me is that the 1/4" plywood is held down with ring shank nails every 4 inches. So the average 12" linoleum tile has 9 nails in it. Its going to take forever to get this floor up. Its about 100 square feet so that would be 900 nail holes.

Do all of those holes then need to be filled? WHat would I use to do the job? I like a floor with character, but will all of those filled holes stick out?

ANd finally I'm planning on putting down Brazilian Cherry for the rest of the floors since I know I can't match old and new flooring....Should I just rip up the old red oak and replace that section with Cherry too?

Normally, I would never recommend abandoning an old oak floor, but this has to be so full of nail holes it would look like heck if you tried to fill them. The black stuff has to be(hopefully), the glue from the first floor.

Clean/sand a small spot and see what you get. Those old growth floors were much nicer than anything you will find today, but it may not be salvagable.

I agree, work on a small area to see what you have. I once worked on a remodel job where they installed used 100 yr old heart pine on the floors, left all the nail holes [some were black but not as many as you have] and finished it with a satin finish - it really looked nice!! although maybe not with all decors.