It's been a while since I've watched it, so I may be shaky on some of the details. I always figured/rationalized that the people being moved around during the crash were not actually moving from the stardrive section (not all of them, anyway. And not the children) but were being moved to designated "disaster locations" where people could be accounted for, to reduce the risk of people being trapped somewhere, unable to call for help, or some other such contingency.
I don't remembeer if t he canon of the film contradicts this possibility, but it worked for me.
And, yes, I always cringe at the whole little girl losing the teddy bear thing. Just one of the worst moments in all of Trek.
I'm also not too happy that the conn and ops consoles on the bridge go flying, instead of being attached to the floor.