This is a topic that you can start a ReligiousWar over.

It should not be taken lightly, and unfortunately it has split the Linux community somewhat. Google gives 50,000+ hits for GNOME vs KDE.

With the recent (last 6 months) release of a new generation of both Gnome and KDE, there are some choices to make. Basically, evaluate both and decide which one you want.

If you like KDE, you might want to look into Mandrake, a distribution that was started because RedHat refused to support KDE in their distribution. If you like GNOME, you have to look at XimianGnome?. There is no simple answer, for good and for worse.

RedHat have recently tried to unify the two for the first time with their BlueCurve theme which basically is a theme/theming engine for both platforms that makes them look the same. This is a truely excellent idea.