Thanks for the roses, Jeanene. In my view, the best floor finish is oil based polyurethane. I have had real good results with Parks Oil Modified Poly. It holds up great. The only negative is the long drying time. I think that you would have the best results by sanding and staining the floor and then 2 or 3 coats of the Parks poly.
As far as putting the tung oil on the floor, you can have several problems. Most of the tung oil sold is not really tung oil. It is a blend of oils that nay or may not have tung oil in it. In any case, this will offer almost no protection against the many things that can damage a floor like abrasion and water. The next problem is that there are so many kinds of "tung oil", you can't make a blanket statement about compatability. As you can see, this is not a good choice.