Desktop environments

[leg.ios at legios.org]

XDM can also do this, although to be honest I've never used XDM, only KDM
and GDM.
There's info in the handbook here:
http://www.freebsd.org/doc/en_US.ISO8859-1/books/handbook/x-xdm.html

I prefer KDM or GDM to handle this task - it launches a GUI (based on QT
or GTK depending on which tool you use) and lets you launch your DE of
choice. There's handbook details for both here:
http://www.freebsd.org/doc/en_US.ISO8859-1/books/handbook/x11-wm.html