I had a Windows computer (with pirated Windows XP). After a "Windows Genuine Advantage" update, my system said that it is pirated and that I did not have a genuine advantage. That basically bricked my XP. It never was able to even boot to completion or work.
I did not use it for 1.5 years and did not miss it in any way and used Linux exclusively at home. I have linux on my server, my son't computer, plasma TV computer and my laptop.
The XP machine was finally fixed, but I no longer care to use it for anything. I also do not like to accidentally get viruses into my home.
Running Explorer on windows is enough to get it hacked.
I also treat that windows box as untrusted.
One person I knew, had a kid's windows computer infected by spam zombie software. That computer started sending spam like mad. Fortunately it was behind a Linux firewall, so we turned it off remotely from work.
IOW, a firewall does not prevent a computer from being infected by viruses, it only blocks *some* scenarios.
Mac is basically FreeBSD with Apple custom GUI. I saw a mac book once and was impressed.
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