Murphy Brown- The episode where her mother died and the episode where she found out she had cancer. I cried when Miles left, but then I cried tears of joy when Lily Tomlin replaced him.
Punky Brewster- I cried when I was a kid during the episode where Henry had a heart attack.
Picket Fences- Too many times to count, but most notably when Zelda Rubenstein died after falling into her meat freezer. Picket Fences was utter perfection.