It really depends on what your overall goal is. If you just want to use Linux for yourself then any of the debian/ubuntu spins are good. If you want to use Linux professionally then its good to be familiar with a Redhat based Linux (ex. Fedora).
Many large enterprises use RedHat or Fedora for their DC/Workstations. Some use Debian bases (ubuntu) but I have not seen that often.
If you want it to "just work" and not have to mess with things as much then Ubuntu or similar are easy since there is a large "user" community behind it and the other spins. You can almost always find a .deb package for whatever you want to install which you might not be able to find a .rpm package if you are on a RH base.
(post is archived)