I'll throw my 2 cents in here...
Windows - good if you play a lot of games or if you wanna/have to buy prebuilt. Needs antivirus etc.
Mac - design is nice, I've heard good things about customer service, immensely overpriced.
Linux - it's free, viruses in theory should never do much damage as unless you're in single-user mode, stuff can't run as root.
Best option for me is custom build + Arch Linux. Too much bloatware around these days with fancy desktop cubes, wobbly windows and other absolute junk that slows your system down and does nothing for productivity. Even graphical login managers... Logging in from a tty and tiling window managers FTW.
And yes, Linux is way better than it used to be for noobs. Problem is, Ubuntu further lowers that bar and you get the blind leading the dumb. IE: "rm -rf is the powerful command to remove files" which you see in every "This year is the year of the Linux desktop" article that some self-proclaimed tech guru has written when they "discover" Linux, or usually Ubuntu in particular.
Also, I'm on Pickin's side in terms of Ubuntu not being a "real" distro, because of the same reasons - Debian base.
And Lurker, don't use Ubuntu due to shorter release cycles - all that's happening is Canonical set themselves up for failures every 6 months. The time between Debian releases is longer for a reason. I used to use Ubuntu and I've never had a version change go smoothly. They should release when it's ready, especially as a lot of their users are inexperienced with Linux.
And as for manually deleting stuff on Ubuntu... kinda pointless. You can't remove anything major without it wanting to remove the core system. Dependencies in Ubuntu are insane. You might as well use Arch if that's the kind of thing you're after.
tl;dr use what you like, use what you can afford. It Works For Me™
... the difference being while all you Windows, Mac, and fake distro users are still watching your loading bars scroll by I'm already in UrT
(sorry, couldn't resist
)