First off, nice job on the lifts. I think those are pretty good for your age if they are true.
Second, if you are trying to put on weight and get stronger I seriously doubt your getting enough food. PLEASE log all you caloric intake over the course of 3 days and post it. At 17, there is really no such thing as too much food. I'm guessing you live with your parents, so eat them out of house and home.
Lastly, I don't really know what to tell ya to start taking. Most all the stuff I have seen on no2 is crap. Most supplements are crap. Creatine is def something you could start taking. Fish/flax oils, a really good multi-v, and protien powder is what I would say. Bio-test has some creatine that I just bought, it was only $12! How can you pass that shit up. Anyways, I really hope you log and post your food, it will help you BIG TIME. Good luck