I am sorry but I had to give my crystal ball to a friend of mine, so I
could not guess which error it was or which form it took. Really sorry.
Did you check the whole wiki page on Virtual Box?
http://wiki.minix3.org/en/UsersGuide/RunningMinixOnVirtualBox
Particularly interesting is the 7th part, #Workarounds
> secondly I want GUI so I need to install x11 .
Once you got MINIX running, you will be able to install X11. Please keep
in mind that MINIX is not particularly oriented at graphical interfaces,
the command line is the only way most of us are using.
> and how to install (VLC , and firefox etc )
I am not sure VLC is available (for instance, I am not sure there are
any way to get audio in MINIX.) And I am sure there are no Firefox
pakcage at the moment. These are just two examples of things you should
not expect to be available with MINIX at the moment.
Antoine