Accessing Menus in Mac OS X via Keyboard
My favorite way to do this is to use the help shortcut (cmd-shift-/), which brings the focus in Leopard up to the help bar. Then start typing the name of the command you want and it will filter the list below to the commands that fit your pattern. Just down arrow to the right one and it will actually show you where in the menus that command exists, along with any shortcuts assigned to it. Hit enter and it executes the command.
This makes more sense if you actually do it :).
This makes it really easy to search through all of your commands for the right one, and in a few keystrokes gives you access to all of the menu items.
Unfortunately this doesn't work anymore in Firefox (where you have to use the old ctrl-F2 way) because they hijacked the "help" shortcut to bring you to a stupid webpage that is never what I want.
Control-Fn-F2, or Control-F2 if you use F1, F2 etc. as standard function keys.
System Preferences » Keyboard and Mouse » Keyboard Shortcuts. Click the + button and follow the instructions.
According to http://www.xvsxp.com/misc/keyboard.php, if you hit Control-F2, you can navigate the menus just like in Windows: Left or right arrows, or type the first letter or so of a menu's name or a menu options name to select it, and enter works just like clicking the option.
As far as changing XCodes menu shortcuts, [you can just use the "Key Binding Preferences" in the XCode prefs dialog. http://developer.apple.com/documentation/DeveloperTools/Conceptual/XcodeWorkspace/300-Keyboard_Shortcuts/custom_key_equivalents.html#//apple_ref/doc/uid/TP40002706-SW2