Continuity mistake: Raphael points out that Yoshi is no 'senior citizen'. He adds "Come ooooonnn..." and in the passage from one angle to another Raph's bandana moved from the front to the back of his shoulder. (00:56:50)
Revealing mistake: Walker celebrates the news that he's gonna get the agreed price on his shipment from Lord Norinaga. He fires his cannon, which not only must be firing a cluster projectile since it disintegrates in a single shot 3 targets, but also it makes them implode. (00:58:20)
Plot hole: The plot takes a turn for the nonsensical when the Turtles find the Scepter and Mitzu walks off. With no explanation (she is the best fighter of the resistance) Whit captures her. There's no explanation on how he did it with such ease, how did he happen to be at the right place at the right time since nothing of what happened was under his control, and even where this 'right place' was, because he is riding towards the village (and the Turtles themselves) with her - just how far did Mitsu wander during Grandpa's very short apology to be captured by someone who gallops to the village to show her off as bargain chip? (01:05:45)
Continuity mistake: When the Turtles are climbing the wall to get into the garbage-chute that leads to the prison, you can see Donatello's bandana tail hanging down towards the wall just as if they were crawling on the floor. (01:09:05)
Revealing mistake: The grate on the prison floor (left open and unguarded after they escaped from there the first time) is made of thick metal...or so it looks, because when Michelangelo climbs up, it wobbles by the lightest tap of his elbow. (01:09:55)
Continuity mistake: After learning about their supposed ancestors, the Turtles begin fighting Norinaga's guards. Michelangelo is the first one in their way and is at a standoff with one of them who has his sword raised, and still the following shot shows exactly Mike facing some enemies that run at him. (01:13:10)
Continuity mistake: In the fight alongside Mitsu, Donatello beats up some soldiers by the table with the scrolls ("Bases loaded, home run"). The scroll is placed in a different, more orderly way than before (when it was on top of another parchment). It wouldn't tidy itself up during the fight. (01:13:40)
Revealing mistake: The rebels broke into the court of Lord Norinaga's palace. Donatello knocks down two guards with a leapfroggin' double flying kick. Which sounds way cooler than it looks, because it is obviously miles away from actually connecting. (01:15:15)
Audio problem: When Leonardo stops Daimyo, the words "Hold it, Bucko" are heard, but Leonardo is not seen to be speaking at all. (01:15:30)
Continuity mistake: The goons with guns arrive at the castle, "There goes the neighbourhood", quips one of the heroes. In one shot Raphael sidesteps towards Michelangelo to reach his arm, in the reverse it's Mike and Don who are restraining Raph from charging. Same mistake happens a few seconds later, when Walker delivers his "Who's your tailor" line and Don is restraining Raph, or not. (01:17:35)
Audio problem: When Walker confronts the Turtles in the Daimyo's courtyard, he says "My God, who's your tailor?" One of the Turtles says "We're naked." but none of the Turtles' mouths move. (01:17:45)
Continuity mistake: In the baffling phase when Whit takes exception to the killing if it's done by guns and Walker just throws him with the others, Elias Koteas moves his gun from the left to the right hand when Stuart Wilson calls for Niles, but in the next shot the gun is much lower. (01:18:15)
Factual error: During the movie, characters may use lingo that would not be understood easily in the time period of their counterparts. April for instance uses the word "cool" in the modern sense, and nobody questions that, but you could assume that they don't understand every word and infer nonetheless the meaning from the context. Walker however when he's about to fire his cannon uses an idiom "Try this on for size" that was coined in early XX century. (01:19:40)
Continuity mistake: Leonardo ducks the cannon shot tucking his head inside the shell with the bandana going in front of his shoulder, but he emerges with the bandana on both sides of the neck later. (01:19:50)
Revealing mistake: It's even too obvious when the movie finale turns into a bit of a farce, but when Mitsu elbows the guards to free herself, it's obvious that she does no damage - the guards are wearing armor, even - and the extras don't do anything to 'sell' the hit. (01:20:20)
Audio problem: The Turtles reach Walker's chambers. Seeing that he's escaping, one of them yells "C'mon, Mikey!" but nobody's lips are moving. (01:20:50)
Revealing mistake: The Turtles give chase to Walker; Leo and Raph run across a roof, but the tiles are obviously fake; look at Raph's feet and you'll see one in particular bending like gum under the push. (01:21:00)
Continuity mistake: For his curtain call, Stuart Wilson acts in close-up like he's losing balance, body arched back. The impact looks all different in the wider angle. (01:22:50)
Revealing mistake: Walker meets his demise in sequence with a shockingly poor visual effect; he falls into the ocean from the cliff, and instead of splashing into the water, he sorta disappears quickly through it. (01:22:55)
Continuity mistake: When Benkei climbs the sewer ladder and disappears into the light, Donatello is touching the ladder in the first shot, in fact he puts both hands on deliberately, but he's not even touching it in the second. (01:28:35)
Answer: I don't belive it has a set name, other than giggle or laughter it is just a generic sound. Much like the Wilhelm, which I think fans named after hearing it in a lot of movies.
NoWhereMan
Ben Burtt, a sound designer who used the scream, is the one credited for naming it the Wilhelm scream. It's named after the character Private Wilhelm in the film "The Charge at Feather River" when the scream is dubbed in after he's shot.
Bishop73