My house is another 75+year old with hard wood floors... I put an old (tightly woven) rug under my sewing table for that same reason... it's worked OK, but I'd rather have a protector mat... I'll be looking for the one without the nubs!! My walls are the old lath and plaster, too... They're a mess to hang stuff, especially shelves... I've been using free-standing shelves.. Let us hear what you end up using??
and Happy Quilting!!