Lunch recommendations near the zoo?
You're very close to the Village, just west of Rice University which is just west of the zoo. There are tons of restaurants located there including many ethnic. My top choice would be Istanbul Grill (Turkish) but there are also a couple of Indian (Shiva, Bombay Brasserie), Thai, Italian, sandwich shops, etc.
Here's a link that's been posted before but the lists are dated so you'll need to confirm from other sources if a place is still there.
Besides that over to the East along Almeda is Reggae Hut, south near Reliant Stadium along South Main and Fannin there will be others.
Oh yes, parking in the village can be tight.
Edit: I saw Istanbul isn't even listed so I checked - appears to still be there!!!