My favourites are the ones with Patrick Magoohan, the one with the two college boys who murdered their professor and made fun of Columbo all the way through, the one on the cruise ship, the one where Faye Dunaway fancied him and she though he fancied her (silly moo) and I really like the one with Tyne Daly who murdered her husband - that do for now ??
I think McGoohan was in 3 episodes? Peter Falk's wife - Shera Danese -was in 6. She never played the killer but conspired with the murderer in "A Trace of Murder".
He was in four dave, but don't ask me the titles, I'm not good at those! Yes, his second wife appeared in a few didn't she ? Also the down and out in that scene where the nun thought Columbo was a tramp, appeared in several episodes too.
Years ago I could watch Red Dwarf and Blackadder over and over again. Same with Friends a bit later. More recently I've been watching Keeping Up Appearances. Love it :o)
Mr Ed was very good, as was Flying Doctor ("Flying Doctor to Wallamalloola base; Flying Doctor to Wallamalloola base; Come in Wallamalloola. I've got a little fella here with a broken leg, his Dad's having a heart attack and their little dog is fittin' or something.")