This is advice for games that are played in person or in a largely synchronous setting like a chat. If you're playing by forum a lot of it won't work well just from your end, and you'll need to establish an alternate gameflow by sharing your players' concerns with each other up front.
The hot-headed fight-happy guy who has to be restrained by the better angels among his companions is a reasonable character to want to play, and you can make it work, but not accidentally.
Nothing happens unless you let it.
Dungeon World is a conversation. When you're having a conversation about where to get dinner and somebody shouts "Jack in the Box!" you don't all just immediately go to Jack in the Box because it's the first thing somebody said, do you? You let everyone talk about where they want to go and make a decision together after hearing what everybody has to say.
In much the same way, when you're describing a tavern scene and mention a cloaked figure, and Grognak's player screams "GROGNAK SMASH!" and pitches some dice, that doesn't actually mean that Leafwillow and Sir Justice have to stand there poleaxed while Grognak smashes through three poker games and a marriage proposal to get at the cloaked figure. You're the GM. You control the universe. Nothing is going to happen until you say it does, and that means that you can take Grognak's input without saying what comes of it, and then turn to Leafwillow and Sir Justice and let them have their say.
How To Stop A Fight
Dungeon World has no concept of initiative order or equal goes. People take actions and get the opportunity to take actions as it is dramatically appropriate.
So, when Sir Justice stands in defence of the tavern patrons and rolls Defend, and when Leafwillow frantically grabs at Grognak to hold him back and rolls Interfere, this doesn't "use up their actions". It's not "Grognak's turn" again. You get to decide how the tavern reacts and who gets the spotlight as a result of it. "I'm going to let go" could turn out to be excellent leverage for Leafwillow to Parley, for example.
This is the usual flow of running Dungeon World, by the way. Everyone entangled in a dramatic situation, and you pick one person at a time to talk to and make some progress on their corner of it. For those times when you're just describing the world and not necessarily looking at anyone for an answer, you're not obligated to humor the first person to speak up - you weren't talking to anybody, so you can wait to hear from everybody.
It Revolves On This
But, again, while "the hothead who needs other people to hold them back" is a fine character concept, it's not one you can play accidentally. If Grognak is fine with being dramatically violent and Leafwillow and Sir Justice are fine with dramatically getting in his way, and letting the fall of the dice influence who wins out at one time or another, that's great. Just actually be sure everybody's fine with that, preferably by asking directly.
It's not really going to work out well in the long run if any of them think they can somehow sneak violence or peace without anyone being aware, talking openly in front of each other to the person who controls the universe. Anymore than you're going to keep having dinner with someone who ignores what everybody said and drives to Jack in the Box anyway.