It sounds like there's something messing up your gnome desktop environment settings.
You should be able to reset it by doing this:
press ctrl+alt+f1, this will take you to a text-mode window. Log in with your normal user details, then type this (on three lines):
mv ~/.gnome ~/.gnome-backup
mv ~/.gnome2 ~/.gnome2-backup
Then press ctrl+alt+f7 to go back to the desktop. Press ctrl+alt+backspace to kill the broken desktop (or just restart the VMware machine).
You should then be able to log in using the default settings.
Hope that helps,
—Robert J Lee