For many people, Yuma is just a wide spot on the road between San Diego and Phoenix. So the following is intended as a guide for the motorist zooming by on his/her way to someplace more important. At least this way you won't have to eat at McDonald's. The restaurants are listed by freeway exit from east to west.
Dome Valley Exit-OK, OK, I know this is 20 miles east of Yuma, but the Ligurta Station Restaurant here is like the old roadside cafes of the 50s. Same smell, same menu, same surly waitresses, same good food. Decent burgers, fries, soups, sandwiches, potato salad etc. Worth a stop.
Foothills Blvd. Exit-Go south on Foothills to the first stripmall on your right. On the southside of the mall, Bernardo's offers good subs and decent imitation Philly cheesesteaks (Sam Bernardo being from Philly). Also the fish and chips place in the same stripmall ain't bad either.
Fortuna Rd Exit-AVOID Tyler's Taste of Texas with its slow service, cramped seating, hokey menu, and mediocre barbecue. Another example of a chain restaurant crowding out a much superior local truckstop that used to be at this location.
16th St Exit-Go east (away from downtown) for a half-mile or so and get burritos and Mexican fast food at Pancho's Cocina (not to be confused with Pancho's Restaurants in town). Located in a Barney's service station, the food at the Cocina is tasty and quick. Plus, you can get cheap gas and visit the rest room at the same time. I've also been told that Los Cazuelos (about a block further east) is a good cheap Mexican place, but I haven't made it there yet.
4th Ave Exit-Go into Yuma on 4th Ave and at the corner of 4th Ave and 2nd St. is Tacos Mi Rancho. This funky looking little place has some of the best Mexican food in town and is highly recommended. Try a caldo if you've never had Mexican soup before. The burritos are also excellent.