virtualbox.org

I am trying to change host key from right-ctrl to something else. All the searches say I should select "Preferences" from "File menu", then "Input" tab. However I do not see file menu. If I press host-home, I see a menu with choices "Machine", "View", "Devices", "Help". None of these has an item called "Preferences". There is a "Settings" item on the "Machine" menu, however it does not have any "Input" tab, and none of the tabs that are available seem to contain any setting for host key. How can I access "Preferences"? I am running Virtualbox 4.3.10 on Ubuntu.

That is found on the main manager and not the guest.

If you need further assistance post the guests log file ( as an attachment )

Moving to Linux host

How can I access the main manager? When I start Oracle VM VirtualBox Manager from the launcher, I get a window that has no menu bar, just a "Settings" button which brings up the same dialog I see when I select "Settings" from the "Machine" menu of the virtual machine. Where can I find the guest's log file to post as attachment?

Ubuntu with unity takes over the title bar of any application window and places it in the top panel.

Is there any way to change the host key in Ubuntu?

No because Ubuntu is not VirtualBox.

Start the main manager and while it is active place your mouse on the top Ubuntu title area. Then you should see the functions you would have seen on the main manager title bar.
There is a way to turn that feature off by the way but that is not a VirtualBox issue. Yo would need to ask Ubuntu how to do it.

Thanks