I've been googling until little fingers hurt, trying to find the best rowing machine. I totally didn't know there were different types, like air, hydraulic, water, etc. I found this site: http://www.listfitness.com/best-rowing-machine-reviews/ but it doesn't really go into much detail. How do I narr...

I agree with Tanukirai. Strengthening you're core is always a good thing, so doing ab exercises will help burn fat and get you stronger. Just don't go overboard until around 10% in opinion. Basics like planks, hanging leg raises, etc. are fine for now.