We've had the “putting them to bed without dinner situation” too. My pediatrician said at this age as long as they have one good meal a day they'll be fine. And to ease my guilt, the doctor told me “he's not going to let himself starve.” I'll tell you one thing, if they go to bed without dinner they eat really good the next day!

My advice is to keep doing what you're doing. It's a phase and he'll eventually start to eat whatever is put in front of him. Have a little wiggle room; pizza night or hot dog night once a week. Also, my older son favors 5 smaller meals (breakfast, lunch, dinner and two snacks) over three big meals a day. And his snacks are always healthy (by his choosing and to my delight!) with lots of fruits, vegetables and whole grains.