Better yet, why not install Google Chrome and replace their Internet Explorer link with a link to Google Chrome? Just make the link have IE's icon so that they don't wonder where the internet has gone. They will marvel about how you "made their internet faster." I like to make it even easier for people by making two different links: one called "Internet" which takes them to Google, the other called "Email" which take…
Then install the following extension to change the titlebars: https://addons.mozilla.org/en-US/firefox/addon/57/?id=57
Finally a bit of desktop shortcut renaming and icon-customisation, and mother will never be any the wiser!