Finish for raw floor

I have Brush Box floor boards which have been hiding under heavily tacked masonite and hidious floor tiles for about 40 years. The timber is in excellent condition (nice and tight) apart from the holes left from the tacks. So here we go...
-Should I try and conceal these holes or highlight with Black oil putty?
-What do I do about the rust layer from the existing floor nails?
-What is a good product for this timber ( in a hallway with kids)?
All suggestions appreciated from this clueless electrician.

A bit of a clueless electrician myself but having just done this for the second time ( a hallway)

I would suggest the following:

- Allow plenty of time to sand the boards. The more effort you give this the better the result.

-get a good quality sander / edge sander from kennards ( around $100 deals for weekend or bunnings have a cheaper mid week option and sand paper is cheaper. This is where you pay.

- Make sure you get all the tacks and nails out or it will cost you a fortune in sandpaper.

- Either get a good match on a water based putty or give the floor an initial coarse sand (if you have the time) and use this dust to fill up the holes.

- Go through all the grades of paper coarse med - smooth. this determinesthe result.

- If you have diverse shades of wood or heaps of holes stain the floor with water based brush box to get uniformity.

-coat with waterbased polyureathane.

Why water based? These days they are as good or better than oil based and definitely less puss & pain.

cheers