" to some truly inexplicable guest stars like country singer Jerry Reed and Mama Cass"

Not really inexplicable:  they were pop stars of the time, same as Davy Jones and Sonny & Cher.

Ya but this was a kids show...Sonny & cher had a popular TV show at the time and The Monkees were still in re-runs.  Mama Cass and Jerry Reed were not exacly popular stars to kids.

 if it weren't for some these episodes I would have no idea who have these "stars" were

After the Simpsons closes out next season, Scooby Doo will still be going. Amazing.

This was probably my favorite Scooby Doo incarnation when I was a kid.  I always looked forward to seeing the episodes with Batman and Robin.  Didn't they use Adam West & Burt Ward to do the voices?

As an aside the new Scooby Doo show, Scooby Doo! Mystery Incorporated has a really cool Easter Egg / Homage in that one of the towns people has the likeness of Don Knotts.