getting engaged

My boyfriend and I have been planning on getting engaged sometime in the next year or two. It's come up and I've told him things such as how excited I would be to be with him and spend my life with him. Nothing too crazy. Now, I have been asking him if I could give him a few ideas on what I'd like. Like pick out 5 rings and show him the general idea of what I would like. I understand how the man is supposed to know the girl well enough to get what she wants without asking her. But that makes me extremely nervous. I would like to make sure he knows what I want. I'm not making him choose from a list or anything. Just showing him what I like. But when I try to talk to him about it, he just yells at me until I cry and then he leaves my house (we live apart). Is it wrong for me to talk about being engaged and showing him what I like?