Mad Men Mondays: Episode 3.2 "Love Among the Ruins"

I don't think I'm smart enough for this show sometimes. I've watched this episode twice and I'm still not sure what was happening in some of the scenes. Also, I'm not sure how I should be reacting to what some of the characters are doing.

Why was Don fondling the grass during the May Pole dance?

What was that long look that Don gave Peggy while she was in her office on the typewriter at the end of the episode?

What was the thematic connection between the different plot lines (the Madison Square Garden storyline, the Peggy hates Ann Margaret storyline, and the Betty vs William dutiful children of senile father storyline)?

I'm so confused!!!! Waaaaah!