I think you're going to have to start from the beginning, because I honestly have no idea what you're asking. There's not really a Menu option to turn "on." You insert a menu, and boom...there it is.

What is the exact text of the item that's greyed out? Are you, by any chance, trying to use the Scene Selection Menu? If so, you need to select a video (either in the Project Overview window or from the buttons on an existing menu) in order to add a scene selection menu.

If you mean something else, please give us more detail on what you've done so far in your DVDA project and what you're trying to do that won't behave as you want.

EDIT: I was recalling this post this morning, and the fog lifted. (But it lifted for GeorgeW first.) Sounds like you're on a menu and trying to edit the Remote Buttons properties. To the best of my knowledge, the button settings you're trying to access are only applicable when the viewer is watching a video not when they are already at a menu. At any rate, the behavior of these buttons (Menu, Title Menu, Top Menu, etc) can vary between DVD players, particularly when the viewer is looking at a menu on the DVD.

Rob