Mission Control Preferences on Your MacBook
You can configure the Mission Control, Spaces, and Dashboard settings on your MacBook. You can use Mission Control to view all the application windows that you’re using at one time so that you can select a new active window.
Or, you can move all windows aside so that you can see your Desktop. Dashboard presents a number of mini-applications (or widgets), which you can summon and hide with a single key.
The settings are
Active Screen Corners: These four pop-up menus operate just like the Hot Corners/Active Screen Corners in the Desktop & Screen Savers pane, but they control the operation of Lion’s screen management features.
Click one to specify that corner as one of the following: an All Windows corner (which displays all windows on your Desktop); an Application Windows corner (which displays only the windows from the active application); a Desktop corner (which moves all windows to the outside of the screen to uncover your Desktop); or a Dashboard corner (which displays your Dashboard widgets).
Choose Launchpad to activate the Launchpad screen. Note that you can also set the Screen Saver Start and Disable corners from here, as well as put your display to sleep.
Keyboard and Mouse Shortcuts: Click each pop-up menu to set the key sequences (and mouse button settings) for Mission Control, Application windows, Show Desktop, and the Dashboard.
You’re not limited to just the keyboard and mouse shortcuts on the pop-up menus. Press Shift, Control, Option, and Command keys while a pop-up menu is open, and you see these modifiers appear as menu choices! (Heck, you can even combine modifiers, such as Command+Shift+F9 instead of just F9.)
To display your Dashboard as a Space within the Mission Control screen, select the Show Dashboard As a Space check box. If you prefer your Dashboard widgets to appear as an overlay (as they did in previous versions of Mac OS X), disable this check box.
Automatically Rearrange Spaces Based on Most Recent Use: If this check box is enabled, Mission Control presents your most recently used Spaces first within the thumbnails at the top of the screen.
When Switching to an Application: When selected, this check box allows you to switch applications between Spaces desktops using the Command+Tab shortcut. Lion jumps to the desktop that has an open window for the application you choose, even if that desktop is not currently active.