In my opinion, the last thing a male dancer would want to do is lift weights in preparation for starting ballet classes.  When you see male ballet dancers looking really buff and cut, it is the result of years in class training every single muscle in their bodies to be supple, responsive, and strong.  A guy dancer wants his body to lengthen.  Weight lifting produces a square body, which does not create the proper "line" for ballet.

Your height and weight sound ok.  What you probably need is muscle tone.  Start taking at least three ballet classes a week.  If you watch your diet, you'll drop 10-12 pounds quickly, and then you'll be in a reasonable weight range for a dancer of your height.  Personally, I finish a good ballet class five pounds lighter than I started with my dance clothes soaked through with sweat.  If you feel you're still not burning enough body fat, swimming is great.

I do a little work in the gym for my upper body strength.  But the lifts you do when you partner a ballerina are mostly done with balance and momentum.  You don't have to "muscle her up" unless she's really a lousy dancer.  So cool it with the weights, and don't over-do.

"Dance Magazine" is a great source of information about schools in your local area.  Again, it's great that at your age you're going to start ballet.  Have a great holiday.

Joe