I'm running vmware fusion 5 under OS X Mountain Lion. My virtual machine is running Ubuntu 12.04.
I have two fastidious shortcuts which I would like to disable:
- When I press Command ⌘, Ubuntu opens the dash and shows under the text field a set of icons.

- When I press the Option ⌥+` keys (which I use for making accented letters) Ubuntu opens the dash without showing the icons under the text field.

How can I disable or block these shortcuts?