My DS eats better if we sit down and eat as a family, or if he can feed me or DH. He sometimes prefers the food on our plate, dispite it being the same as his, just not pre cut up. Also he has his own utenstil and will feed himself with it or by hand, I will have one too and can slip in a spoonful or several during the meal.
The first time we made pizza DS would eat some of the topping while preparing it, but would not eat it after it was cooked, I had cut it up in bite size pieces. Second time, I cut thin pizza slices, he ate almost 1/6 (1 slice) of the pizza which I think is reasonable for his age, he had something to eat earlier to.
You sometimes have to keep presenting the same foods several times before a child will eat something, sometimes it is quite unusual stuff they will eat. DS likes smoked fish and tinned smoked oysters, though not prawns.

Good luck, hope your DS expnads his variety soon.