I don't like Ubuntu. It's Debian with a paint job and newer packages. My personal opinion of course. It has potential of course which has yet to be reached.

If a GUI is what you're after distro doesn't mean a thing since the GUI in Linux BSD and UNIX is something you can install yourself and use whatever you want. SUSE by default, has a nice one.

I have a Slackware box with Enlightenment E17 which puts most GUIs to shame. So in other words, use whatever you want, and look for window managers and desktops like KDE and Gnome and pick whatever looks good to you.

Ubuntu is very very different in the way root works which for me is a pain in the ass so I only used it to test and nothing more. I generally use SUSE and Slackware for Linux, and FreeBSD for BSD.