I really hate the episode "Kiki's Kitten". I wish it doesn't exists.
Not only Runt makes a cameo in his own show, but also this short feels off all the time. The duet Rita does with an alley cat is horrible and so is the "humor" in this short (Gorillas at the Ritz? seriously?). I have a copy because I honestly have no other option but... I don't think I will watch it ever again.
I also have a lot against the premise behind Buttons and Mindy. It's just unfair to the poor dog... almost outrageous. Katie Ka-Boom was alright but repetitive (and her only cartoon that I really enjoy is the one co-starred with Chicken-Boo).
I was absolutely disgusted at Rita's treatment in that Kiki episode. By far the worst Rita and Runt short.
However, my most hated episode is White Gloves. It scared the living crap out of me as a kid and plagued me with nightmares of headless things.