For me, it has to be the Aids episode. I really felt for the father in the end, they didn't show us what happened to him. If I was to lose my family like that, being the family orientated person I am, I would probably end up committing suicide myself. Who is there to live for? what is the point of living, if you cannot share it with the people you love? But that is just me, choosing the easier route to end the suffering and pain.
As for the episode itself, how harsh is the society? Like Karan correctly said in the end, it wasn't Aid that killed that family, it was society. The rejection, the dirty looks and no acceptance, warm or love from anyone is what took their lives. It was the lack of knowledge, the lack of education that aid is not contagious by simply touching the person, or sharing food with them, it is spread by direct intimacy or through blood transfusion.
I hope, after watching this episode, all those insensitive ppl who by their behaviour and attitude kill the affected people will think twice before treating them like that.