It started w/ 1 & 1/4 in 2x2 ribbing, which I did. It then says Rib 4, (rib2tog, rib 4) 15 times, rib 0. 79 sts. I think I have the rib2tog part figured out, but what would the rib 0. 79 sts mean?
What pattern are you doing? What are the actual full instructions?
Usually when something says K0, P0 or the like, it is because directions are give for multiple sizes and some of the sizes don't do all of the steps.
You should have 79 stitches left for your size. If something says "0", just ignore it.