I liked season 3 mainly for Renamon and her evolution line as well as the setting being in the real world where Digimon is just a card game and an anime. Oh! But Jeri goes crazy tho.
My faves were Season 1 & 2. I still have my black D3 even though it probably doesn't work anymore
I liked the more serious tone of season 3. Jeri was a really interesting character in that not many shows directed to younger audiences ever really address the topics of death and depression so boldly. I even remember thinking "Damn, this ***is dark" back when it first aired. I still get tinglies from Biomerge Digivolutions.
I keep my blue card that came with my D-Power on my desk just in case it, you know, activates.
I really liked The Killing, especially the first season.
Holy ***, the ending to the series made me cry like a baby >.> I dunno exactly what it was. I mean, on paper it should have come off as really corny and forced, but I was just like, "Baaaaawwww, they're finally happy T_T".