Linux distributions have been going in and out of fashion. Distributions aren't important -- the point is what can you do with your favourite distribution.
I had tried OpenBSD, FreeBSD, Slackware, Redhat, Fedora, Gentoo, Arch, Ubuntu, and Debian. Theres not much different. They are all *nix. Newbie should force themselves using command lines, a little scripting, compiling kernel and such. Plus, read more UNIX/Linux books rather than specific distribution. From here, distribution of any kind to try out will be a breeze.
Currently I'm using Ubuntu. I prefer the minimalistic Ubuntu-server(base system) installation. I can have everything I need(fluxbox, mplayer, maxima, latex) within 10 to 15mins plus further customizing for 4 seconds bootup
Anyway, Donald Knuth(mathematician and computer scientist) uses Ubuntu. Linus Torvald uses Fedora. So think they are newbie too?
I don't really care about the distribution. I just adore the art of linguistics that linux/unix provides