I couldn't get my son to stop throwing food either (he's now 16 months). So I finally thought of time-out and it worked liek a charm. He still does it occasionally, but he used to throw everything at every meal, so it's much better. I say "Don't throw" and IMMEDIATELY put him in the boring laudnry room for about one minute. It really devastates him (so I usually get him sooner than 1 minute because he learned his lesson) and when I go back I say "Don't throw" again and then we hug and kiss and I let him know that I still love him. Not all kids respond to that, though.
As for veggies, my son is pickier now, too. I guess it's a way of asserting their independence. What has worked is to offer him the veggies first, and not let him eat anything else until he eats the veggies. Eventually he gets hungry enough that he'll gobble up the tomatoes and cucumbers, or whatever. I don't feel bad like I'm malnourishing him, because the food is available the whole time and it's his choice. But I don't do that too often because it's just easier to let him eat what he wants and not always worth the battle to me. But I just make sure his alternatives are also healthy, like fruit, whole wheat pretzels, yogurt, boiled eggs. Maybe try focussing on the vegetables she does like, if any. And my son loves to dip things, so that works (but then they just keep dipping and sucking off the dip without eating the vegetable sometimes). I also try to set a good example and eat lots of veggies and say Yum Yum. Also we recently discovered that having the spoon be an airplane or train really does work. He ate the whole bowl of food that he had previously refused to eat once we made the spoon move around and make noise.
Hold on there, because they do start to understand as they get older. And just keep talking to her like she understands and eventually she will. I was amazed when just this week I told my son that he had to eat one more bite of vegetable before he could have the crackers he kept pointing to. I seperated one bite of veggie and put it in front of him. I kept repeating it, adn then he finally ate it and I made sure to praise him and follow through with the crackers I had promised. I actually think he understood, but your child probably has a couple months before she completely grasps what you're saying. I also started telling him if he doesn't want something to put it on his tray in the corner instead of throwing it. Adn I show him. If I'm consistent, eventually he'll figure out what I mean and start doing the same.