Depending on when was the house build it might contain asbestos or might not. I would suggest you get this thing tested and if it doesn't contain asbestos you can rent a small jackhammer with a scraping tip and clean up the floor pretty good. If the floor is not leveled get a floor primer and then , self-leveling mix. If it contains asbestos it will be a price job to remove it and dispose it, but health doesn't have a price sticker on it and you don`t want cancer because of breathing asbestos dust. Best of luck!