I said XFCE..
Back when I used Linux, it was on my 400mhz craptard PC, so I didn't want the bloat of KDE, didn't want to find and download Gnome, and XFCE had the little mouse. ^^ Anyways, I liked XFCE due to its being lightweight, having multiple desktops (although I wish I could have figured out how to splitscreen them if I needed to), and I liked the fact that you could just drag across the screen to switch desktops. Plus, the "start" menu was a right-click away, I think.