I too had the same problem w/ a house that I purchased. I used BIX stripper on the floor because the floor sander kept gunking up every 5 feet. I had to do this in the LR, DR and Kitchen. May sound like a big job, but it really wasn't. After I got all the grime, glue and stain out, I sanded. It really turned out great. I do have a few spots that you can tell are bad, but it is worth it! We had Oak, so went w/ a dark Minwax stain, but not too dark. Hope this helps.