Family meeting and phrases to eliminate

We had our first TSG family meeting today. The 4 and 2 year old were told to sit on the couch on their own section and be quiet and hold still. They wouldn't do that for long, so we spent most of the meeting just correcting toddlers. The 17 yr old thought the meeting was just about her shortcomings.. and well, that is all we really got around to talking about. She should unload the dishwasher before or after seminary, and she should use her day planner. We don't have a unified family vision or mission statement yet, but we did create a couple of rough drafts at the three day parenting conference in October. What could we do better for this meeting to go well next time?
I've noticed we use some phrases in our family that when I hear them, I raise an eyebrow and wonder, "Is this a phrase we should be using? Does it help create the kind of family dynamic and attributes we want?" please comment on whether there is a place for these phrases or if they should be eliminated:
"Don't you dare:"
"Now!"
"I told you!.."
"DO YOU UNDERSTAND?!!"
"THAT IS UNACCEPTABLE!!"
"Give it to me, NOW!"
"If you don't ____________, then I will take away your __________."
"Watch yourself! You cross your legs. You sit right here. You put your hands in your lap." 17 yr old correcting the 4 yr old in calm down spot.
"This is not OK!"
"You are gonna listen! You hear me?! (finger pointed in face of toddler)
The frustration level with the toddlers is getting really high. They don't follow instructions half the time. And they both struggle with no answers about 80% of the time. The four year old won't stay in bed for naptime. She sneaks out and plays in the room, or even gets into the crib with her 2 year old sister. They typically keep each other up for most of nap time. It seems like we have to correct correct correct, and it makes getting anything else done difficult. It's just one extra chore after another. Then we use the calm down spot. Sometimes we goto the calm down spot even if they are calmly disobeying, but we have already assigned two extra chores. But, they get upset being sent to the calm down spot, so then they do need to get calm. And, we test them with following an instruction upon exit of the calm down spot. Then we talk, and do some role playing, sometimes. The two year old says the funniest things, and is usually so cute, it's hard to crack down on her with the extra chores. The 4 yr old wants control everywhere. Help!