WM's are window managers. Unlike a full-blown desktop environment such as KDE or GNOME, window managers only manage windows. They don't provide things like desktop icons, file managers, etc. To get those, you have to install programs yourself, like iDesk or thunar. Some WMs are Openbox, Fluxbox, Xmonad, awesome, and dwm.

Try Minix, it's not Linux but it is what got it started! When I used it at my university back in 'old days' the install disk was a diskette (well, maybe 3) and the box was an old PS2.