My wife and I are moving into a house with beautiful hardwood floors
that have been hidden under shag carpet for years. The carpet and pad
appear to have left the wood it almost new condition (1950's)

I know fully refinishing hardwood is either expensive to have done
professionally and an enormous amount of work to do yourself. So, I am
looking for a simpler way to treat the floors prior to our move-in.

Is there a problem with simply applying a coat or two of modern
polyurethane to make sure the surface stays in great condition? If this
works, would I have to lightly sand the surface first or could I just
apply the polyurethane after a good cleaning?

I have not closed on the house yet, so I haven't' been able to test
the current surface for water absorption, wax, etc.

Thanks in advance for any help