The shiny coat might have been put down by the previous renter, but I doubt it. More likely, it was the owner, hoping to attract another renter.

There's really nothing that will hide the scratches. I know it's a nuisance, and it will look blotchy for a while, but it's actually a good thing that it's coming off so easily. The quicker the better. You can speed up the process even more by using an green abrasive pad with your floor cleaner.

Once it gets uniformly worn down, a "finish renovator" can be used to bring up a soft gloss. The floor will actually look much better and be easier to take care of.

If you want a professional to take a look at it, I'd suggest using the National Wood Floor Association website to find one one in your area

http://www.woodfloors.org/consumer/findPro.aspx

The stickiness of your kitchen floor is almost certainly due to something like Brite or Mop-n-Glo. You can get that off with some "no-scrub" stripper, available from your local janitorial supply store. I'll give you the details when you're ready to tackle it.