Well i suggest start running also. Running burns the most calories per minute than any other sport except for cross country skiing. I would not suggest running everyday since you just started because of overuse injuries. I would suggest taking atleast one day off and starting slow then building up. If running gets boring try rollerblading, cycling, swimming, tennis (burns alot of calories), jump rope anything aerobic will burn calories and fat. Resistance training will build muscle. Now if you run you will have muscle TONE in your legs but not necessarily mass. I suggest a combination of both for the best results. Since you havent a gym try pushups and situps. If you dont have any weights pushups is the best resistance training exercise for the arms since it works most of the muscles.

hope this helps. im an exercise science major so if u need more advice ask.