After running a VM and logging out, I got a black screen. I powered off and re-started but got the same after the bios option in start up passed. Several attempts went bye with the same result. So I fiddled with bios boot options a bit and was able to get to a different looking Ubuntu start up screen which, after entering pass key would run a series of commands that were too numerous and frantic to make out. They appeared to be overlapped/layered (the text that is) and seemingly repeating endlessly. I had to power down to get it to stop and re-booting just had the same effect. Finally, I hit the down arrow key when prompted for "disk sda5_crypt" at the pseudo Ubuntu log-in screen I mentioned before. This brought me to an all black screen which read something like:
lvmetad not active cannot process volume group "umbuntu-vg" unlock disk sda5_crypt**
From here I entered a password and Ubuntu start up ran.
That was an unsettling hour or so and I'd like to avoid that in the future. Any ideas what caused it and how to avoid it going forward?
Should have said this before but Ubuntu is the only OS on my machine and my optical drive cannot be opened manually.