Just like to add that I run Kubuntu on a spare machine that I have now and again. LOVE it! I like KDE much better than GNOME, but it's a personal preference I guess.
I think it looks a lot more advanced and clean. You can always install GNOME as well, or install Ubuntu, then install the KDE package so that you can use all of the standard GNOME progs under KDE.
Have fun!