I can use the mouse to navigate the system and most programs easily, except for some strange programs (e.g. 'writing' or document programs) that change the TAB key to inserting a tabbed space rather than changing menus. Usually things are possible with alt keys but it's a little harder and occasionally the program doesn't work right. (In my school's Office 2007 I found it impossible to access one of the options I needed with the keyboard, even though I could find everything else easily)