Help, I'm new at this hardwood floor stuff. We moved into a home about 10 years ago, it had carpeting then, we removed it and replaced with new carpet. We now are thinking about removing the carpet. House is about 80 years old. Hardwood looks to be about 2 inches wide. nice redish color. Carpet padding has been stapled, and carpet strips will have to be removed. There is a white residue under the carpet padding, not solid, but in a random pattern. I'm guessing this is part of the padding. These hardwood floors have been covered up for the last 20 years or better. This residue can be removed by scratching your finger over it. What can I use to remove this 'padding' without damaging the flooring??

may need to be sanded..