Main Menu to show only parent pages and not all of them

Hi,

I’d really love to be able to fully customize my menu(s). For example, my site (http://crowneurope.eu/) is currently showing all pages in the main menu. Instead, I would prefer to be able to determine which pages show up in the menu. In addition, I would like some of the child pages to not show up as sub-menu items at all.

How can I do that?

Thank you very much!

Andrew