Most computer users use the browser for basically everything so when people say "Linux isn't ready for the masses" they are showing their ignorance, Linux runs a web browser just fine. There are plenty of rock solid stable Linux distributions and the person doesn't even have to mess with a terminal if they don't want to anymore. Though yes the terminal does make things faster. Linux has gaming down pretty well now though not perfect yet but that's mostly a  game development issue not really a Linux issue and office tasks work on Linux as well. So I don't know what more you really need our of a computer especially at a casual user.