I second Robin's.
We also hit El Cholo on Fair Oaks. It's big, noisy, full of families, and the fresh chips hit the table almost immediately--great to appease munchy toddlers. There is *definitely* better Mexican to be had in the area but the tableside guac is delish and I've had good luck with the specials. The waitstaff are very kid friendly, too and there are kid menus with crayons.
When our toddler is feeling relatively mellow, we've also had good luck at Noodle World on Colorado, maybe because our kid is nuts for noodles. It's not geared to families but the food comes quickly and the young waitstaff and clientele are very laid back and don't seem to mind a little bit of squawking and squirming.
Not sure if you are looking for a restaurant that an adult will actually enjoy too. ;)
I think overall a good option is El Portal (mexican). We had a group dinner there with a large party with several toddlers and they were fine. Ask for an outside seat if it's not too chilly. At least it's easy to walk the kid around when he gets impatient. http://www.elportalrestaurant.com/
Places my son enjoys more than I do are Gelato de Roma at Old Town (pizza and gelato), and Red Brick Pizza on Lake. Red Brick have TVs with individual controls and DIRECTV in each booth so that always seems to work as an electronic baby pacifier. Both places the pizza are decent, not Mozza but better than Pizza Hut and the like.