Maggie2...
My now seven year old was probably one of the worse eaters around (other than my nephew who now really only likes KD and fries...). We fought with her every step of the way and tried TONNES of things... if she didn't eat her supper it got put in the fridge for the next morning, no dessert, no bedtime snack unless she ate supper, made her try new foods every meal, one time I even put her supper in a tupperware container when we went out for ice cream and wouldn't let her have ice cream until she finished her supper!
Well, I've got to say that in between 5 and 6 she just started eating more and more... now she pretty much eats everything on her plate and when I look back at the battles and struggles and tears it just wasn't worth it. I know if my brother survived growing up on grilled cheese, spaghetti and fries that anything could be better than that. That being said, we didn't fight with my second, who is now 5 and tries everything all the time because she says that "your tastes always change when you get older" and granted she doesn't always like everything but meal times were more relaxed and enjoyable without the fights. So, now with our third, there are no fights, we just always offer it to him and if he eats it great and if he doesn't, he might the next time.
Good luck with whatever you choose to do and just try to enjoy your meal times with your family.