First you should know that you can run the plain Mythfrontend without a window manager. Though if you want to start external programs, like Xine or MPlayer from MythVideo, you will need one to get the new window visible.
Some window managers in use
(The first 3 are strictly speaking Desktop Environments, but well, that includes a window manager.)
- KDE, recommended if you use your system under Linux as workstation too.
- Gnome, another desktop system for Linux
- XFCE and XFCE4, light weight, though 4.0.4 and 4.0.5 seem to have problems with focus of MPlayer, Xine and Ogle.
Light weight window managers for dedicated myth boxes
( Your choice of window manager should take into account whether this is a work station that happens to run mythtv or if it's a dedicated mythtv machine. A dedicated machine has no need of the CPU and memory waste of the Desktop Environments and it's usually best to go with one of the smaller light weight WM's such as these)
- IceWM A very small and configurable window manager
- Fluxbox, a BlackBox based window manager that is much lighter than KDE but with a good feature set
- Ratpoison extremely light weight windowmanager, works fine with external programs.
- EvilWM, no borders, window decorations or icons. Small binary size.