(Yes, of course we'll dispose of the old stuff if you don't want it!)
Removing a wood floor can fall into two levels of effort. Much depends on what the original glued to or what type of adhesive was used and how well it was installed.
Removing wood sub floors is likely to be the most time consuming and troubling. Generally it’s more advisable to forget tearing it out and install another sub floor over top, but depends on what type of flooring you’re replacing it with.
Chances are great once the removal begins not only does the wood floor come up but parts of the sub floor with it. Pursuing it to completion and you’re likely to have a sub floor torn and shredded, possibly even weakened if larger chucks come out?