Not enough bandwith to describe my favorites - loved the Cincinnati references albiet some were negative - The Who concert tribute - Sparky as a sports-talk host - Herb's line about Les' manual in case communists invaded Cincinnati (HERB: Who's going to invade us? Dayton? If they did, we'd kick their butts)
If pinned down - I'd say the episode with Sparky, the Turkeys, and the one that some TV Network wanted to do a show about WKRP-and the TV network made up a "Bizzaro" WKRP - where Les got walls.
It was a very good series - some were just stupid - but most made you think.
FWIW - and DANGER AT YOUR OWN RISK - someone's got all 90 episodes of the WKRP for sale - (they are located in Canada)
WKRP on DVD