Batman TAS

Because I rather like the Justice League Cartoon, I thought I'd give the Batman Animated Series a try too. So I now have copies of most of the episodes of Batman The Animated series, plus the first season of the Gotham Knights series. Almost 100 cartoon episodes, yet with no real time for a cartoon marathon of watching all episodes in order in my immediate future. Hence I've been wondering which episodes are the highlights? Which ones are essential for cartoon continuity, the mytharc episodes so to speak? Any recommendations which eps I should pick from those of you familiar with the cartoon?