Parts of Peurto Rico are amzing- but be careful!! LOL, last time we were there we got lost and stopped in this neighborhood because we saw a police officer. We got out of the car and walked up to ask him directions; he turned around, was wearing a bullet proof vest and said "you need to leave this neighborhood right now! Get in your car, lock the doors and I will come tell you how to get out of here."
There are def some really bad areas around San Juan- Didn't see many south of the Island.
PR is also a great place to surf or bodyboard. If you ever wanted to try it- PR is the place.
If you go to Puerto Rico go to the South Side of the Island! It is much nicer. There is great shopping in Old San jaun but not much else. on the south end of the island the beaches are much better, and its much more laid back. Also if in Peurto Rico you must go to Culebra. Take a taxi to the town of Fajardo and there is a ferry that takes you to this semi-deserted island off the coast od PR. It has one of the top 10 beaches in the world. I have been to most of the Carribean and Culebra hands down has one of the most beautiful beaches I have ever seen.
http://www.destination360.com/caribbean/puerto-rico/culebra-island.php
http://www.islaculebra.com/index.htm