Please allow me to share a few universal, immutable Truths about the wood flooring found in older homes.
When you hear the words "... and there's a wood floor under the carpet," what you should think is: " ... and the abused damaged ruined remnant of a once-beautiful tongue and groove plainsawn oak floor lie beneath this urine-stained berber."
Carpets are generally put on top of wood floors for a reason, and in my experience -- this 50's ranch being my third, after two early 1890's Vic's -- those reasons have a lot more to do with concealing/cheaply covering up damage than it does with comfort, sound or any other very plausible explanation.
In the my Vics, the carpeting was there to hide termite damage. (Termites, btw, like nice tasty oak floor better than icksies pine subfloor). In the case of my '50's ranch, it was to cover over a profoundly flowerpot-water damaged floor.
It's also worth noting that some floors, even if not all that "damaged" are basically ruined.
For example, in th case of my 50s ranch, in addition to several pizza-sized water stains, when i pulled up the chihhuahua-pee stained carpet this morning i found 4d or 5d nails -- facenailed into every flooring strip, at every joist for a grand total of . . . 1500+ nails. The floor cannot be refinished in this condition, and it cannot be simply patched, as every face nail needs to be removed before i can sand, which effectively means every strip has to be pulled up.
Better to buy a whole new brace of 3/4" oak, given the prices of oak today, plus it gives me a cheaper material to practice floor sanding on than the maple i'll be installing later this year in another room.
I should hasten to point out that i'm far from upset, and I am definitely not complaing or unhappy -- this gives me a great excuse for MORE TOOLS, (like that excellent pneumatic cleat driver i saw at Berland's) along with a great opportunity to level floor, which, had i not needed to remove the old finish floor, i probably would not have taken the time to do.
.max