macos - How do you use a Mac without a mouse?

So I was using my Mac Mini and decided to set the application button on Logic Click mouse to open Exposé. I had this set up at one time and found it useful. So I open the Exposé control panel and took a look at the triggers for Exposé. There is drop down for a secondary trigger. In that drop down there was a ton of mouse buttons 100+. So I selected #32 just to see what button #32 was on my 5 button mouse.

Turns out it's all of them!

Headdesk

So no matter what button I press guess what happens... I get Exposé.

So using the just the keyboard how do I:

1. 
   

   Change the Exposé trigger?

   
   

   I can use the keyboard to bring up the control Exposé panel but guess what I can't get anything else to come in to focus.

   
   


2. Kill Exposé?

Right now all I can say is D'oh!

Any ideas?

EDIT

Also I should mention it is an older PowerPC G4 processor.

Booting into safe mode doesn't help.

Answer

Control-F7 is a toggle that will "Change the way Tab moves focus" -- either between text boxes and lists only, or all controls. You want the latter.

Note that with some keyboards that put other functions on the F-keys -- I have Rewind -- you also have to press fn; so fn-Control-F7 should let you Tab to those popups. Space to open the popup, arrow to the selection and Return.