The name is indeed Moonchild (or Moon Child, depending on your preference).
If you don't understand it, it gives you *you* a chance to name the Empress, which brings you into it a little more. Just like at the end of the original Time Machine movie, he takes 3 books back to the future, but it isn't revealed what that are.
It is his name, at least in the movie, Bastian's line "What a shame they don't ask me. My mother, she had such a wonderful name.." reveals this.
It is my favourite movie of all time. I've seen it more times than I could possibly remember. It is a part of my childhood, it's a part of me.
When I grew up, I was shocked to find out how many people had not seen it.
However, my fiance loves it as well, so that makes up for it. ^_^
Also, if we have a boy child, we're naming him Bastian.