Lots of people seem to like ubuntu linux, and from what I've heard it's fairly easy on beginners. Ubuntu's based on debian linux which is what I use, mainly because it has probably the biggest collection of packages of any linux distribution, but debian does have a bit of a learning curve (I've always had to solve a few problems when installing from scratch - but when it's running it's pretty stable)

In any case, any recent linux distro should give you the option of a fully functional X server + one or more desktop environments like Gnome and KDE and a few more "minimal" window managers.