I am still using Ubuntu 14.04 and it is a worthwhile choice for the desktop. The stability of the desktop is fine now, that is with the default Unity desktop as well as the KDE 4.11 desktop environment. There are other desktops available, such as E17, Awesome, and Xfce4, but I like to use Unity or KDE as my desktop. The Fedora 19 Linux distribution is also a good choice. The 13.10 Ubuntu distribution that caused so much trouble is no longer a problem as long as the 14.04 release continues to be problem free. Ubuntu is the dominant Linux distribution owing to the advertising clout of Canonical. It should at least offer a bug free Linux experience then. This is what the potential users expect out of a Linux distribution. They want to install it and get things working out of the box. So it should be able to offer a quality desktop experience. It should be clear from the outset how to install updates and install/remove software from the system. That would make it even more popular. Linux Mint is taking over from Ubuntu though, as it has an easy to use Linux distribution. I know there are other Linux distributions that I could be using, but I like Ubuntu. I am glad I could get rid of 13.10. If you have 12.04 still installed, I would stick with that until the final 14.04 release comes out. Skip 13.04 and 13.10 and just wait.
To install libdvdcss in 14.04, use the package that is available from this site: http://download.videolan.org/pub/libdvdcss/1.2.10/deb/libdvdcss2_1.2.10-1_amd64.deb. I installed this package and DVD playback worked like a charm. Just download the deb package and install it by typing this command.
sudo dpkg -i libdvdcss2_1.2.10-1_amd64.deb
That is the only thing that I could not get working easily on Ubuntu 14.04.
There is also a way outlined on the community Wiki to get this installed: https://help.ubuntu.com/community/RestrictedFormats/PlayingDVDs#Installing_libdvdcss. Thanks to the commenter on this article for pointing this out.