I've eaten at both of these places quite a bit. I like Tony and he's helped me out of a few jams when on the island so I always recommend him since his food is always good as well. But I can't say the cooking there reflects local cuisine. La Choza will be the more authentic local menu for you if that's what interests you. It also happens to be my favorite restaurant on the island. Love their fajitas, chicken in black sauce, that salsa, the margaritas, the murals in the bar, etc..... Damn, I love everything about that place!
Tony's is probably the more kid friendly but La Choza isn't bad.
Both places are fairly close to the pier, but back in a few blocks off the main street.
Crap, now I'm hungry!