@ Kernel Kwatz!
Pretty much all (desktop oriented) distros are the same for a while when you're first learning Linux.
After you've used Linux for a while, you might be driven to other distros for a variety of reasons, usually based on your learning style and/or experience.
A while after that, you generally settle on Debian. (opinions vary on this, but so far that's the pattern). I'd avoid pure Debian at the outset though.
It's important to remember that Apple's OSX has One Look & Feel(tm), and Windows has (what amounts to) One Look & Feel(tm) as well.. but Linux desktops can have literally any look at all. Whatever desktop Linux you wind up running, keep in mind that you are NOT married to that graphical interface, and you can pick and choose which GUI you want in a preference icon at your graphical login prompt (whichever one of those you happen to be using at the time).
Every (desktop oriented) Linux distro will also come with (what amounts to) a( graphical)n App Store.. In fact, the whole App Store(tm) craze (made popular by Android and iOS) COMES from Linux's model of application package repositories.
Keep in mind that installing anything outside of the App Store (or in Linux parlance, package repository) is generally frowned upon, because (much like in windows) it's much harder to manage software which doesn't come from the package repositories. Fortunately, there are (no kidding,) tens of thousands of applications in any given Linux distro's application package repositories.
The vast majority of software available for Linux is in your distro's app repo, regardless of what distro you land on. This includes the GNOME's GUI, KDE's GUI, XFCE, LXDE, Enlightenment, and any of the other lesser known GUIs for Linux, so you have a lot to choose from. They're also entirely interoperable. I highly recomend installing all of them (drive space is cheap), and just futzing around with them til you find one you like. (people will call me crazy to suggest this, but they should try it too.)
Remember, when picking a (desktop oriented) Linux distribution, that they're just that; -distributions-. They are collections of software (GNOME comes from gnome, KDE comes from kde, Libreoffice comes from libreoffice, pidgin comes from pidgin, etc etc) that each distro gathers together from their respective sources, packages, and sticks in their respective app repositories. So if something does work on one distro, and doesn't work on another distro, it doesn't necessarily make one distro better than another, what it means is there's a configuration difference (80% of the time) which is causing the issue.
Some distributions of Linux are better assembled and maintained than others, and some should be avoided altogether (I'm looking at you, Gentoo) if you're a newbie.. But (except for Unity, which i personally don't like) you can't really go wrong with whatever you land on, armed with the understanding that all distros are collections of the same stuff.
Linux can be a bear to learn if you run into problems, but keep in mind that the whole world is out there to help you, unlike calling Microsoft or Apple support, you can literally ask anybody you know that uses linux for help and are sure to gain some insight (including "don't ask that guy for help again"). Remember that nothing Just Works(tm), not on OSX, not on Windows, and not on Linux either. The key difference is, though, you can generally *find* an answer for Linux problems. This usually involves asking people, trying things, and not giving up. For the most part Linux is successful because we all try to help each other. Linux isn't made by a company, and Linux isn't a failure, so we must be doing something right, hmm??
My opinion of good starter distros are Fedora (it's boring and stable) and Ubuntu (just pick a different GUI cuz Unity is teh gross). Cinnamon is my favorit GUI this week, but LXDE is what i log out and switch to for gaming because it's a good balance of uses-least-resources and has-minimum-number-of-features-i-like-in-a-GUI.
Another US$0.02++
