Launcher 1.2.1 crashes: OpenGL?

The kids play, so unclear what got them to the new version, 1.6.2, but that's when this started. They tried to launch Minecraft and it crashed with the text in the attached Word doc.
I've reinstalled the minecraft.dmg,
i've checked the latest version of Java is installed.
And I looked at whether I can update the graphic drivers, but you can't on a Mac, of course.
I've tried to launch earlier version, 1.6.1 and 1.5.2 via the 'edit profile' option.
Kids can't play Minecraft since we upgraded.