X11 hangs on exit

Hi all,

does anyone know an easy to read manual for newbies introducing X11 - more specifically how to open windows, resizing them, etc...?
I namely installed FreeBSD 7.0 on an old HP omnibook xe4100 notebook because it's less demanding in resources. So far so good, everything went smooth except when leaving the graphical environment. The laptop hangs, the screen goes black. I tried to use xinit and startx to get X11 running (which they both do well) but both result in the same problem when quitting. As I understood from the BSD handbook the xinit is used to automate or script the startup of X11, not really to start it. Can this problem be related to the graphical interface?
I selected the generic interface when installing BSD since the Neomagic Magicgraph NM 2160 - NM 64 was not listed in their db.

A second question I have (probably a very stupid one) is about the terminals in unix: could one run x11 with for instance Opera and the other terminals continue to function in normal text mode?

Many thanks in advance,

erik