Lip bursting into The Jockey to save Ian from marrying into the Maguire clan.
Lip: Call it off! CALL IT OFF!
Marty effectively cremating Craig's father.
Marty: Everyone should go how they want to go
Possibly a Crowning Moment of Heartwarming, Awesome and Funny mixed in to one.
Sheila: "This is a normal family home." Considering the context of the line, awesome!
Frank talking Tom out of killing himself over Debbie.
In the American series:
Carl using his bat on a guy that held Lip out a window.
When Sheila Jackson has partially gotten over her fear of being outside. Her reason? To get Liam back inside the house after he had wandered outside.
She overcomes her fear even more when she chases her estranged husband out of the house after he drives their daughter into a sobbing, destructive rage.
Fiona not merely chewing out her own mother for abandoning them but also for trying to take Liam away as well.
When Sheila cusses out Peggy Gallagher during Karen's party. Sheila asks Peggy, "Why did they let you out? Because you're a loud, mean vicious bitch" and then shouted, "you've got a demon mind and a devil's womb!" ...At which point Peggy pulls a gun.
What makes this even more awesome is that only a few days later Sheila let's a sick Peggy stay in her house and takes care of her as she is dying. She does so out of pure kindness and Peggy even apologizes for her earlier bahaviour.
Sheila stealing Karen's baby from the hospital after the would be adoptive parents copped out.
Tony's partner not deciding to bring in Sheila on kidnapping charges in the Season 2 finale.
Estafania attacking Frank with a frying pan after he attacks Ian, ranting about aggressive men like her abusive ex, Marco. The sheer catharsis of that scene, both for her and for the audience, due to how they're likely infuriated with Frank beyond the point of forgiveness by that scene, is incredible.
Veronica going WILD and getting Cheryl to sign her and Kev's divorce papers after Cheryl calls Kev a stupid piece of shit.
Ian doesn't get as many badass moments as you'd expect from an aspiring soldier, but there's a little moment that shows just how badass he is. When Mickey is going nuts and beating Lloyd (Ian's older sex partner), Ian pulls Mickey off and than proceeds to knock him over with two fingers to the clavicle. Of course he runs off with Mickey, turned on by Mickey's jealousy, but the fact that Ian could beat Mickey, the violent gangbanger with zero effort is telling.
From Emily, Mickey and Ian fighting Terry, who ends up getting a No-Holds-Barred Beatdown. Want something better ? When the police comes to stop the fight, Mickey taunts Terry about the likely Prison Rape that awaits him, one cop tells Terry that he is in real trouble now, due to getting in trouble not four hours into parole, and another cop lets Mickey go because he happens to be gay too.
Also from Emily. Lip's and Amanda's rather ingenuous ploy of extorting Amanda's Jerkass father, whom was bribing Lip in not seeing his daughter anymore. The best part? Amanda comes back to Lip later saying they could have gotten at least 20 grand or so, but Lip never seen 10 grand in person before and took it.
In 5x02, Fiona's boss kicking the ass of a costumer being rude to Fiona, as well as not tipping her for the large order she served.
Later he beats up a guy for slapping Fiona, when she slapped him first, after he tried to grope Debbie.
In that same episode, Mickey and Ian's revenge prank against a homophobic minister. It involves getting Mandy to seduce the minister, take him to her house, having him look away while "Mandy" gives him head, before switching places when one of Ian's gay army buddies switch places with her. Ian, Mandy, Mickey and the other buddies proceed to take pictures of him and post it on the internet with Mickey saying...
What are you going to say the your congregation ? You thought it was a teenage girl ?