The two places I know of are Vallarta Adventures and Sea Life park. I have taken my daughter and her friends to Vallarta Adventures twice, with nice results. I have been to Sea Life park, but only to use the water rides--and only 3 out of 9 were open :( So, based on my limited experience, I would recommend Vallarta Adventures. Also, I would recommend the more expensive tour, as the amount of interaction with the dolphins is much greater, as well the group sizes smaller. Hope this helps :)
Lynn