If Open Office won't start...
… upgrade your nVidia graphics driver.
I just had the problem with Open Office crashing with the following message on start up:
** (process:4772): WARNING **: Unknown error forking main binary / abnormal early exit ...
All googling brought up unrelated stuff but /usr/share/doc/openoffice.org/README.Debian.gz told me about checking my nVidea driver and upgrading to 9629 really did the trick.