[CentOS] Help with gnome terminal

I am experiencing a problem with gnome terminal, most likely caused by something that I have done and which I need to undo.

The problem is that somehow the gnome configuration has been changed so that the "Contents" menu item under "Help" in Gnome Terminal has the character "space" mapped as a keyboard accelerator. I would prefer that this be mapped to just about anything else, in fact, nothing at all would be best.

I have gone to system/preferences/keyboard shortcuts/ and it indicates that "Launch Help Browser" is mapped to F1. There does not seem to be any other entry therein relating to help. How do I set this to a benign value or return gnome terminal to its default settings?

Regards,