Help, I have a picky eater!!

Hi, I am a pre-nursing student (start nursing school in Sept.). I have a 20 month old son who I can't get to eat well. He was on soy milk but now he doesn't like it. He use to drink it all the time but his doctor told me that he was to old to have it in a bottle and warmed up. Ever since I made the change, he would not drink milk. I tried warming it up for him, putting it back in a bottle, making chocolate milk, he just doesn't like it. I was thinking about using cow's milk, but wasn't sure if it would be good for his system.

Next, he only's likes to eat french fries! I know it's my fault b/c I been on the go alot and don't have enough time to cook 3 times a day. The only healthy meal that I know he will eat is oatmeal in the morning.

I must say that he does eat yogurt and fruit almost everyday. When a meal is prepared you have to make him eat. Sometimes I think that he doesn't like meat or side dishes.

Anyways, my question to you is what can I do to make sure he gets on the right track of eating healthy and what can I do about his dislike of milk?