It's been all about floors here, like no fooling. Remove noxious carpet, behold in potentia pine and have at it with Kwik Strip, 000 steel wool, murphy's and all of that. When you've removed the dirt, ancient varnish and associated gloop apply beeswax. Works like a charm.
OK, there's a different path, another route. Rent an industrial sander and take those floorboards back to basic. I've done it before, several times, but this time didn't. Why? Because the old pine looked good as is and's going to look better with more waxing.
The finish builds, you see,
LSP