That is probably not possible.

• Customizable Shortcuts: https://addons.mozilla.org/firefox/addon/customizable-shortcuts/
• http://kb.mozillazine.org/Keyconfig_extension

Nearly all of Firefox's keyboard shortcuts use the Alt or Ctrl key (the exceptions that come to mind are Backspace for Back and various function keys such as F1 for help and F11 for full screen). If you rip those keys out of your keyboard, you should be good.

But seriously, if you have this issue with multiple applications, you could try a system-level utility such as KeyTweak: http://www.bleepingcomputer.com/downl.../keytweak/. Note: I haven't tried it myself.