I am finally replacing the old sheet vinyl flooring in our kitchen and elsewhere in the house with wood floor. We don't want laminate (we want real wood), but are seriously considering engineered wood because of its moisture resistance.

So is it necessary to tear out the vinyl flooring first? And should I just glue together the floor rather than attach it to the vinyl or subfloor? What if the subfloor is not level? Can anything be done to level the floor short of tearing it out, cutting joists, etc?