We also shopped all around Coronado and San Diego. If you ever are in the area, you must have Mexican food. We had amazing Mexican Food in Old Town and Cafe Coyote. And yes, I do believe we had a Margarita with every meal =)
We then took the Ferry from Coronado to San Diego to the Gaslamp District. An amazing area in San Diego with tons of stores, bars, and restaurants.
I firmly believe you are never too old to go to the Zoo. The San Diego Zoo is huge! I highly recommend wearing gym shoes as the terrain of the zoo is crazy with steep hills! Definitely wait in line to see the pandas - the wait was well worth it.