I've been using Ubuntu for 3 years and just never bothered to switch away to another distro. Before I started using Ubuntu, I had a Windows Vista laptop, and I just wanted to migrate to some Linux away from Windows. Chose the most popular option.
Since I began, I've had two major issues. A failed upgrade from 11.10 to 12-something put me between a rock and a hard place. I couldn't find a way to fix the upgrade or restore to a clean state without reinstalling the OS. Eventually, I just installed 12.04 LTS because I could install it from Windows. The other major issue was my wireless not working (Realtek on a Dell Vostro from 2009). I had to install the wireless drivers from source code (Ubuntu installation tools didn't help at all) and then reboot a few times to get it working.
I use Linux primarily because I wanted a first-class *nix command line: bash, GNU core utils, etc. When this laptop dies, I'll probably switch to a Macbook Air.
I highly recommend starting with either Ubuntu or Crunchbang and then moving to Arch. Using Arch will force you to learn much more about Linux and will make you appreciate many of the things that you take for granted.
Ubuntu LTS CentOS OpenSUSE
Some people swear by Mint or Debian but for most people, there is little to no difference from Ubuntu. Even for servers, using the Ubuntu server install to build a headless server is quick and simple. After that, install something like Docker to install any other services that you require.
I happen to run Ubuntu LTS on the desktop with the GUI reverted to Gnome Classic. There is a package to add that option. But I run CentOS on servers most recently.
I used to run OpenSUSE and only really switched because I needed to get a more balanced experience with other distros. My last OpenSUSE server was a XEN vm host and OpenSUSE made that much easier to set up than plain XEN on OpenSolaris which is what I had used before.
One note about a GUI environment. If you can, leave it off the base server and install it with Docker or KVM or Virtualbox. This may mean that you have to manage two servers in one, and use the CLI a lot, but this is a good learning experience. Modern computers are so fat and fast, that we forget how Linux was in the early days, filling a T1 line using a 486 with 128M of RAM and a 512M hard drive.
According to distrowatch, the order is:
1. Linux Mint
2. Debian
3. Ubuntu
Me, I prefer Mint with MATE because with just a few patches the screen is much more readable than any other distro and it is based on Ubuntu, so I have something to fall back on.
Otherwise I would use Arch.
Mint has been consistently winning on Distrowatch since 2011, the year Unity was released.
This is just one poll (although a pretty large one), but Reddit does an annual poll. Ubuntu is still killing it.
tl;dr: As of now you can have the very best fontrendering in Arch without compiling some patched stuff from the AUR or elsewhere, just by adding his binary repository in pacman.conf. It's top notch. Seriously.
Pacman (package manager) is simply amazing and easy to use. Unlike other Linuxes, you know exactly what you are getting when you run the install script.
Lightweight. Nothing gets in your way. There is nothing to uninstall and there are no hidden spywares to opt out of.
I'm sure there's many other benefits. I tried Ubuntu and hated it. It would take me far more time to get Ubuntu to a level I liked (mostly stripping out the gunk) than it did to install Arch the first time.
The documentation is simply incredible. Not only is the documentation excellent for the OS, it is excellent for all of the things I've used out of the package repository and AUR.
I'm not a hardliner, but it would be hard for me to consider using any other distro at this point.
I first used Arch about 2 years ago at the insistence of someone on Slashdot. I was reluctant to try at first due to the comparative weirdness of pacman ("weirdness" is relative) but found myself quickly hooked. I only wish I could remember the username of the kind soul who pointed me toward Arch. I'm indebted to them for being so kind as to offer suggestions to my repeated prying, and I hope that I can one day extend the same kindness toward someone else.
However, it's worth mentioning that Arch isn't necessarily for everyone. You must follow news updates periodically and keep an eye out for updates that may require manual intervention. Worse, if you're lazy and fail to update the system for a significant period of time (usually 6 months but typically 1 year or more), you might encounter circumstances where upgrading the system is difficult or can only be performed in stages with intermediate packages. The disappearance of arm.konnichi.com (sort of a roll-back machine with older packages) sadly makes incremental updates of older systems difficult, but I think the final set of transitions to the latest file system layout bringing Arch up to par with many other distributions that are currently undergoing the /usr merge effectively renders many of these problems moot. But, if you're studious and regularly update the system, you'll rarely have any issues. Suffice it to say that like what dizzystar wrote, Arch often stays out of your way, but it does need a little lovin' now and again.
My first exposure to F/OSS operating systems was through OpenBSD and FreeBSD, and although I later migrated to Gentoo, I've always had a fondness for the BSD spirit of simplicity and fantastic documentation. After Gentoo, I again migrated to Arch and haven't looked back. The regular recompilations in Gentoo, particularly of X, KDE, or Firefox, started to wear me down and sent me looking for alternatives, but I couldn't bring myself to adjust to Ubuntu or its kin. That's not so say I dislike Gentoo, of course. I really do enjoy Gentoo, even now, and I greatly appreciate the work the Gentoo team does (I still make use of Gentoo for a few things, mostly in virtual machines); I just reached a point where I wanted to enjoy the benefits of a rolling release distribution with the benefits of binary packages, and my time availability is a little less than it was when I used Gentoo. Arch is in some ways much more automated than Gentoo (and in other ways, it requires more manual labor), but all things considered it's the best of two worlds: Rolling release and binary distribution.
Arch with KDE is probably one of the best combinations you could ask for: You benefit from eye candy, usability, a fantastically stable platform, and updates to software packages almost immediately after their release. Moreover, the philosophy of Arch is one of keeping upstream packages as vanilla as possible, so there's little that needs to be done in terms of eradicating obnoxious and invasive package customizations. Even larger packages like KDE are identical to what you'd get if you compiled the sources yourself. I can't say the same for other rolling release distributions like Aptosid which customizes so many of the base packages, it takes time to reconfigure things if you don't happen to have a preassembled set of dotfiles to copy from (which you should anyway). But, I'm not much of a fan of Debian-based systems, so I'm certainly not free of some selection bias.
Ultimately, it's really about what's the most familiar to you. If you like Debian, stick with it. If you like Redhat, stick with it. If you like the BSDs, Arch or Gentoo might be a good bet. If you don't want to spend any time learning Linux distro internals, sticking with a "training wheels included" OS like Ubuntu or Linux Mint might be better options. Arch has the advantage of the Arch User Repository, though, so the selection of software available to Arch users is far superior to many other alternatives.
If you're curious about how Linux works, I'd start with Gentoo or Arch.
1. Arch Linux on three laptops and one desktop all running encrypted btrfs root filesystems, and two Raspberry Pies each running their roots off of 1TB, unencrypted ext4 external drives.
2. NixOS on an Asus Eee PC 900HD netbook with an unencrypted XFS root filesystem. The functional language for the package manager and system configuration, as well as the interesting package pool symlinking, makes for a unique GNU/Linux experience. I use this for Common Lisp coding and server administration when I'm on the go.
All systems run StumpWM as their desktop environment, though the Pies are usually running headless as a simulated OpenVMS cluster, and dual torrent seed boxes.
Windows 7 on HP laptop (procured (wink) from my wife) for taking to university. Runs my CFD and CAD software which only run in Windows.
OS X on Mac Mini on my desk. Bought for iOS development but getting used less these days as I'm back at uni.
Ubuntu on Thinkpad in the bedroom as a media server with Optoma HD600X projector connected.
I tried using the Ubuntu Thinkpad as my main machine but I really just get more happiness and satisfaction from Windows.
Also, fyi, http://askubuntu.com/ is an incredibly helpful resource if you choose any of the Ubuntu distros.
[1] http://mattoncloud.org/2013/07/18/fedora-19-on-a-macbook-air...
Very versatile linux distro and always updated with the latest packages.
Unity is nice when it works but gnome seems to work more often so that is what I prefer.
I've had some thoughts at looking into FreeBSD but that's not Linux.
are you use any osx only apps ?