Thanks everyone! Have done the simple solution adding custom css and the menu is now not displayed
On to next menu problem: I've been asked to also modify the menu on the right, the user menu that shows throughout the site and links to grades, forums, profile, etc. The idea is to only leave the links to user preferences and logout and hide the link to Debates, Forum, Calendar and Grades. Can I comment these out? In which file? I'm not sure I can add this question to this thread or if I'm supposed to open a new one?
Cheers
Trine