Trackbar Gesture for Mission Control / Spaces: Two fingers + click Up until Snow Leopard I was using a simple shortcut to navigate through Spaces (Desktops). Two fingers plus click would present Spaces and allow me to select desktop and/or window effortlessly. So my question is, how can I do that and start Mission Control instead? 

Thank you for all your help in advance.
On a trackpad:
slide with 4 fingers up to open Mission Control
slide with 4 fingers to the left or right to switch to another 'space'

On a magic mouse:
you can dubble tap with 2 fingers ( don't click ) on your mouse to open mission control

But assuming you have a mighty mouse ( your nickname ) you can assign Mission Control to a hot corner. Go to System preferences -> Mission Control -> and press the hot corners button to change or assign the hot corner you want.

Also you might want to check out BetterTouchTool which let you define al sorts of gestures on your magic mouse, normal mouse, touchpad and or keyboard. Assigning them to whatever you want. ( like opening Mission Control )