Possible solution - With a fresh mindset this morning, I attempted to print (from Stickies), and when it crashed I sent a report to Apple. Looking closely at the report, one of the possible offending things (disclaimer - I'm NOT a programmer) seemed to be something called "hpImaging.framework" It was, or was generating, a file that had end char problems. I removed its folder to the desktop, attempted to print, and, lo, the print dialog box came up, no problem. I can print to either printer, it's worked in a handful of apps so far, and, as far as I can tell, has not affected the functionality of my HP printer.
Am I playing with fire, removing such a file? Please advise if you know anything. I will report back when I've had time to thoroughly test things. If this works, then, Jeff, you may want to generate a crash report and look closely to see if something similar is happening to you.