Anyway, you're already here, although I told you not to enter!.
My favourite Linux distribution is Mageia. There are more very good distros (Mandriva, OpenSuse, Debian, Fedora), but I prefer this one. Switch into linux, and forget about viruses, anti-viruses and all that crap. Your computer doesn't have to die because the industry decided so.
Use LibreOffice. Don't be afraid of download it, because it's free (both as speech and as in beer). From now on, all your docs will look like the very same, even if you change the computer or the version.
The PHD comics Strip: jokes for graduate students!