It's completely understandable that you want to know what is going on during your own wedding ceremony and the prospect of it being held in a language you don't speak would be terrifying! Please don't worry you have a few different options. The Playacar Palace offers 2 types of weddings, Civil and Symbolic.
I'm not sure which ceremony you have chosen, but in case you don't know the difference, a civil ceremony would be the legal one and would be recognized when you come home. A Symbolic service would be for you and your guests, but would not apply legally. As for your resort the Civil Ceremony would be held in Spanish unfortunately, there is no option to change this. However, they do provide a translator so you would basically have both languages being spoken throughout- maybe a nice authentic touch since you are getting married in Mexico?
If you don't like the idea of having the Spanish at all and would like your ceremony to be held only in English you would be able to have a Symbolic Ceremony. There would be no Spanish involved in this one, then when you come home (or even before you leave), you and your Fiance could sign the papers at home for a small fee, and be legally married! Hopefully one of these options makes it easier for you to make your decision and you don't feel like your only option is to start shopping for a different resort.
Good Luck and Enjoy
Kielah- Blue Petal Destination Weddings