With my picky 11 year old - I try to look at a menu with him online before we go......
I do the same thing with my 82 year old vision impaired Mom!
Seriously, this is an excellent suggestion for anyone with food issues, allergies, or even budget constraints.
I would also like to add:
Call ahead and find out if a restaurant is child friendly before taking the whole family. If they don't have booster seats or a kids menu, look elsewhere. Be honest with yourself about how well your children can/will behave in an adult setting.
Be realistic about wait times. If you had to circle the lot three times to find a parking space, chances are you'll be waiting awhile for a table. If your goal is to make the 8:00pm movie, a 7:00pm dinner at a popular sit down restaurant may not be a good choice.
If you realize after being seated that the restaurant is too expensive, doesn't serve what you like, uses MSG, etc., it is okay to tell your server you've changed your mind, pay for your drinks, and leave. It is NOT okay to just skip out, or to berate/complain to the staff about things beyond their control.
It is also okay to ask to see a menu before being seated.