A matter of flexibility and pointe?

I had ballet training for three years when I was young, and many other forms since then (ballroom, waltz, hiphop, etc). I know what pointe feels like but injuries forced me to quit after a few days.. I am 18 now and looking to start my ballet training again. What stretches would improve my flexibility the fastest and when could I start pointe again, uming I start over. Also, what is the best dance studio in Boca Raton? Thanks.