What is the best weight loss drug for me?

I was just wondering if there was anybody that knows a lot about weight loss and that could help me. Here is my situation. I am an 18 senior at high school and kind of not in to popular crowd. I weigh a whopping 290 right now and it is taking a toll on everything. I haven’t had a girlfriend in like 3 yrs and I will probably not go to prom. I am a video gamer which I know does not help at all and I enjoy all the food that is bad for me. I used to be an avid mountain-biker but due to my knees I can barely ride it let alone handle the drops encountered on a trail. I snowboard but I can’t really do jumps and things like I would love to do because of my knees. Don’t sell me short because I sit around a lot and eat junk because this just started again because eating healthy and exercise was not working. I have honestly tried everything that I can do without spending too much money. Here is my dilemma. I absolutely don’t want to go the surgical route at 18 so I’m planning on going the pill route and hope some of these commercials are true. Remember this is after trying everything else and now I’m coming to the “experts” on yahoo to help me chose which weight loss medication or anything else to do. Please help me as I am getting depressed and my knees do not stop hurting anymore. This is kind of MY last hope.