The scene [spoil]where the rats were all working together to cook the food for the customers [/spoil]was the scene that made me cheer the most in Ratatouille.
Mitch: Whoops! Sorry! I completely forgot! 
lennonluvr9 - Haha – hakuna matata, dude! 
Here is one from the Incredibles.
I was watching the feature Vowellete and it was a Violet test animation to Sarah Vowell’s voice. I cheered because it was such a cute and funny scene and it was one completely extra.
Uhh, that part isn’t exactly cheerworthy, but it makes me chuckle.
~~=oP
For me, any time in MI when Randall is physically attacking either Mike or Sulley, but especially Mike. 
I’m not one to encourage violence, but there are times when there just isn’t any other option… 
Toy Story
Woody and Buzz’ reunion with Andy at the end of the movie
A Bug’s Life
Everytime when Flik runs fast (For a little fella is he really fast^^)
When Flik gots the idea with the bird, runs away, comes bacvk, kisses Atta on the cheek and runs away again
Bird construction
The celebration after the bird construction
The fight against the grasshoppers
The end
Toy Story 2
Buzz and the other toys go off to rescue Woody
Woody meets Jessie for the first time
Buzz reminds Woody that he is there to make a child (Andy) happy
The plane scene
The end
Monsters, Inc.
Sulley encounters Boo
All the other monsters encounter Boo
Meeting the snowman
Return to Monstropolis
Door chasing
Sulley meets Boo again
Everytime Mike hurts himself
Mike causes the child to laugh hard at the end of the movie
Finding Nemo
Marlin discovers only one egg after the encounter with the barracuda
First day of school
Nemo gets kidnapped
Marlin meets Dory for the first time
The shark scene
The jellyfish scene
Meeting Crush
The whale scene
Marlin and Dory meet Nigel
Marlin and Nemo reunited
Nemo encouraged the fish in the fishnet to swim down
Every scene with the Tank Gang
The Incredibles
Jack Jack shows his power for the first time
Bob meets Edna
Helen meets Edna
Frozone looks for the suit
Dash runs on water
The fight during dinner
Cars
The racing scenes
Lightning and Sally goes for a drive
Tractor tripping
Every other scene with Mater
Every scene with Guido and Luigi
The poor couple lost in the desert
Everyone at the Piston Cup recognises the famous Hudson Hornet as Lightning’s crew chief
Mack commentary about the actor from the movies the sses at the end of the movie
Lightning and Sally meet again after the Cup
Lightning shows Sally his Radiator Springs style
And I’m sure I forgot to mention some XD
That is quite a list there WON!
The entire ending of Ratatouille makes me cheer the most , just because the movie is just so well-done, and the ending is just great. I love it. 
Oh I can agree with you there. I was cheering that Remy achieved his life-long dream. But at the same time, I felt it was very heart warming.
Here’s what I remember from experience:
Toy Story 2: When the door opens and the cleaner is revealed to be Geri, my sister and I in that sea of audience members shouted out- ‘GERI!!’ And we didn’t care if anyone said anything.
The Incredibles: When Dash realizes he can run on water, laughs, and as he takes off, so does the jazz ensemble playing. That just was a great moment.
Cars: Guido’s pit stop moment. It took me completely by surprise and me and many at the world premiere started laughing and applauding.
Ratatouille: The moment between the man and woman struggling with the gun, before they finally give in to the passion. It’s such a fun riff on those old couples who fight become romantically attracted again bits. I still laugh and clap at that scene.
ABL: When Flik gave that awesome speech and all the ants united.
Monsters, Inc.: When they were able to get back to the factory from the Abominable Snowman’s lair.
Finding Nemo: When they got out of the whale.
The Incredibles: When Sydrome’s cape caught him in the turbines of the plane.
Ratattouille: When Collette sees “Anyone Can Cook” in the bookshop window on her motorbike. I actually literally stood up and clapped at this part, and some other people did, too!
WALL-E: When [spoil]the ship defines ‘dancing’ as WALL-E and EVE fly above the AXIOM.[/spoil]
Ooh, those are great scene cheering choices you guys.
Let’s see:
Toy Story: When Woody “comes to life” and Sid freaks out, when Buzz is “falling with style” after breaking free of the rocket
Monsters Inc: Randall getting beat up in the trailer
Finding Nemo: When the fish pull the net free
The Incredibles: Pretty obvious here, when they finish off the Omnidroid and the civilians are coming out to cheer.
Cars: Pushing The King across the finish line
Ratatoullie: When Ego drops his pen
WALL-E: [spoil] As soon as his eyes start going through their “test run”, and the closing moment, when WALL-E and EVE lay their heads together in contentment [/spoil]
I see that you picked some of the most climatic moments of the movies.
And welcome to PIxar Planet. Artemis.
Thanks for the welcome!
And yeah, those moments are just the natural thing to go to, I guess.
That is true. But are there any others besides the climatic moment where you cheered as well?
That scene is so cool! 
In my area, no one cheers during a scene. We just stay quiet. What a boring place to live 
Toy Story – Either the first five minutes or every scene in Sid’s house.
A Bug’s Life – When everyone gets together to build the bird contraption.
Toy Story 2 – Geri fixing up Woody.
Monsters, Inc. – The door scene! The door scene! THE DOOR SCENE!!!
Finding Nemo – Riding the current with Crush or [spoil]when the tank fish “escape” while still in plastic bags. “Now what?” Haha![/spoil]
The Incredibles – Dash running on water.
Cars – [spoil]Lightning McQueen braking before the finish line[/spoil]
Ratatouille – By far, one of my favorite scenes from any movie ever made was when Anton Ego ate the ratatouille dish. His reaction was surprising but completely relevant and touching at the same time. Oh, and it was really funny seeing what happened to Skinner and the health inspector. That always gets a laugh out of me.
Wall-E – Wow, I don’t know yet! Maybe the whole hands-holding part.