Well aren't you just precious!
Do tell what's the name of that private little world of yours - the one where you think everything is completely secure at all times and there are no viruses, scammers or hackers; no one to steal your personal data and take out a crippling, ruinous debt in your name that your whole family won't hope to pay back in the next 200 years!
The choice of your operating system MATTERS! It is worth spending at least a few days pondering your options. A few days to drastically decrease the chance of needing to spend the next 50 years of damage control because of a punk-ass hole in your operating system security.
By the way, the name "Narnia" is already taken.
Look, I suppose that for someone like you, who has a bit more years behind him than there are head (at least that's what you claim to be by your age), it doesn't really matter that much to you if someone does manage to do some damage, but for the rest of us, those consequences can be a lot more drastic, something that may make paying alimony for that slip could have potentially done in their twenties look like a minor inconvenience in comparison.
Even if life is too short to worry about your OS, it is still worth sinking some time into it to make sure that whatever time you got left on this world doesn't turn into living hell.