Thanks for your info and suggestions.
Neither of the second and third listed printers are connected in our house or home office.
The HPP1200 was in the past, but is not now. The Lexmark never has been.
I followed your suggestion to look at the Admin page, and yes, "Show printers shared by other systems" was checked. So, I unchecked it and saved the change.
It seems to be working now. I'll keep checking on the status of my other problems
UPDATE - June 6, 2012 print problems resume today. I sent a Libre office document to the printer (to print 4 copies) and it printed 3 copies and quit. Plenty of paper and ink. Printer works fine from other computers on the network. The "Document Print Status" shows the requested document as "processing." Went into the control center and clicked on cups "start" to stop and restart cups. No joy. So, I cancelled that print job and tried to send the same document to the printer to print just one copy. No joy. So, I looked in the PCL control center and saw that there are now (again) three printers showing with none shown as the default printer.
As I've previously reported, there is only one printer connected on the network. The other two are non-existent, but I still cannot find a way to kill them off so they no longer appear.
I reset the one valid printer to be the default and tried to print again. No joy.
Here's a new screen capture showing the status: http://www.upquick.com/temp/printfail.jpg
How can I get these non-existent printers completely removed?