If it's crap ... We'll tell you
I was 10 at the time of this so don't hold it against me.
In Terminator 2 when the Truck tire rolls out of the inferno a guy in the audience yeld "He's in the tire!!" We all laughed.
Only occasion I didn't find irritating was from personal experience. It was 2000, and my Mom and Dad took my sister and I to see Me, Myself and Irene. Since we were a family of Jim Carrey fans, after all. They knew it was rated R but my Dad figured it wouldn't be anything I haven't already seen or heard. So it was my first R-rated movie in a theater.
Anyway a scene comes up with Jim Carrey pulls out, if I remember correctly (it's been 8 years since I've last seen the movie), a dildo. And my then ten-year-old sister yells "What's that, Mommy?!" The audience laughed and my Mom sank in her seat.
As for recent memories, whenever a kid said anything in a theater it was something stupid, annoying and painfully obvious.