The line in any episode that I relate with Tony more than anything is Episode 9 of Season 1, "Boca". It's the episode where the soccer coach has sex with one of the girls and Tony decides not to kill him.
Tony comes home drunk and is stumbling around while Carmela tries to help him. Meadow is watching from upstairs and Tony says
"Carmela, I didn't hurt nobody. I didn't hurt nobody."
Gets me everytime :'(
And as a side note, when Corrado shoves the pie in Bobby's face because she told everyone about him going down on her. Such a brilliant moment when he leaves the office and it shows the look on his face. It actually kind of pisses me off how they turned him into a nutter in Season 5 and after.