I recently updated my Lucid Lynx installation with some new updates, and here's what happened:

I go to launch Firefox, Gedit, Openoffice.org, Geany, and Kate, among other things, and Metacity crashes. It crashes when I open all these apps.

Next, I try to remove gtk2-module-rgba (what is causing the Metacity crashes), and APT wants to remove ubuntu-desktop for dependencies! Of course, I had to cancel the removal. I now see that /etc/profile.d/gtkrgba.sh has Openoffice.org, Gedit, Geany, Firefox, and various other apps in it already, including Metacity (at the very end). Yet Metacity is still crashing! Why?!

For those of you who want to know my hardware: I have an Acer Aspire One AOA110-1545.

ubuntu-desktop is there only because it depends on all such packages. You could safely remove it if no other package is to be uninstalled.