I got very lost somehow. I removed the # from the fstab file, but then on shutdown, the OS reported failures which flashed by too fast for me to read, but they did involve sda5.
Next, I'm no closer to understanding why I can't or shouldn't use the remaining 280gig for /home? I have no other OSs that should "share" and believe me, the trouble with ONE os is enough. I'm a food writer, and get hurt easily just touching a keyboard (just kidding).
Lastly, please look at the attached screenshots. How on Earth is it Possible that a disk can be "unmounted" and operating at the same time?