As a follow up to the post on kids' menus, this link from CSPI has some great information which reveals that chain sit-down restaurant "kid menu" items are often not any better for your child (or are worse) than fast food.
Be sure to download the Kids' Restaurant Guide pdf file. As I mentioned before when discussing the whole kids' menu vs. real menu issue, quite often the best thing you can order for your child at any restaurant is a second plate and a healthy regular menu item to share. Given the portion sizes at most restaurants, no one will go hungry.
If you want to take the "vote with your fork" approach one further, take the family to a locally-owned restaurant that serves local foods and has healthy menu items. Be sure to thank them for their efforts.