I installed VirtualBox on Ubuntu 12.04 with no problems. But when I install virtual OSs (my goal is to create a virtual Windows network with XP and 2003), my screen "snaps" and removes all icons and menus from my display. Not even the virtualbox home screen shows up which would enable to switch between OSs.

I can't access my server 2003 because I can't get to the v-box CAD function. It seems my Ubuntu box freezes and I am with no choice but to init 0 and start over.

Please advise if yiou can. Thanks, Crackouch.