In truth, the whole first movie is a very lighthearted take on some very serious situations. Let's look at our main cast: Fiona, alone in a tower, and in reality would be completely insane from solitary confinement. Shrek, living, you guessed it, alone, because his only view of the world is that it hates him. Donkey, friendless, but a hopeless optimist. Farquaad, ruling, yet again, alone, with a Napoleon complex and no one but a magic mirror to keep him company. Hell, the whole cast is just lonely, before anything else.
Also, when Donkey first asks Shrek his name, Shrek pauses a bit and finally says it in the tone of someone who barely remembered something. Shrek has been alone so long that he's almost forgotten his own name.
Shrek has a pretty good one. In the beginning of the movie, the 3 bears (Papa, Mama, and Baby) are arrested by Farquaad's men. In the middle of the movie, you can see a bear skin rug with a pink bow on its head on the floor of Farquaad's bedroom. At the end, when all the fairy tale characters are freed and dancing, only Papa Bear and Baby Bear are seen. That means that Mama Bear has been killed and skinned.
Even worse: way before the scene with the rug, you see Baby Bear and Papa Bear sitting around a fire in the swamp. Baby Bear is crying, Papa Bear is comforting him, and Mama Bear is nowhere to be seen.
There's another one. Near the end of the movie, Farquaad is eaten by Dragon when Shrek and Donkey crash the wedding between Farquaad and Fiona. Fast forward to the dance party mentioned above: Farquaad is singing "Staying Alive" while inside Dragon's stomach. He's never seen in the movies after that point, suggesting that he was digested alive.
Either that, or that's his ghost in there, as featured in the spinoff theme-park attraction.
All three bears appear alive during the "Karaoke Dance Party" on the DVD. Farquaad is also seen, albeit in Dragon's stomach, so whether it is canon or not is up to you to decide...
Fiona spent the vast of her majority of her childhood in complete isolation, with absolutely nobody to talk to, just waiting for rescue. The musical explores just how terrible this must have been in the song "I Know It's Today".
Spending upwards of 20 years alone in a tower with nothing but storybooks? By all accounts, Fiona should be completely insane from solitary confinement.
The Logo Joke shows the DreamWorks logo turning green and popping out ogre ears, in the night. It's doing Fiona's transformation!
How does Donkey know the way to Duloc when none of the other fairy tale creatures do? He's first seen essentially being fired from a gig as a beast of burden. He probably used to pull carts there all the time.
When Shrek and Donkey are joking about Farquad's diminutive size, it looks like a continuity error to the kids, since they'd never seen Farquad anywhere except up in the castle balcony where one couldn't see how short he was. We grown-ups, however, are more likely to notice, based on Shrek's earlier crack "Do you think maybe he's Compensating for Something?" that they're not joking about Farquad's heightbut rather about hislength, which for obvious reasons they didn't see any need to check to support their assumption that he's rather lacking in that department.
During Shrek's fight against the knights, he's clearly eating up the attention from the crowd, even waving to them to keep it going. After a lifetime of being hunted down and ostracized for who he was, the positive attention must have been really refreshing for Shrek.
Towards the end of the film, Donkey encounters Dragon, utterly heartbroken and crying her eyes out. It might seem a little strange and maybe even unrealistic that Dragon would be so torn up over losing a funny little creature she'd just met and had known for maybe 5 minutes, but consider where Dragon was when we first encounter her. She's chained up in a volcanic castle keep and forced to act as a guard dog, obviously against her will, and she's been there quite a long time. Dragon was probably INCREDIBLY lonely, and it's easy to conjecture that none of the knights, warriors and whatnot that came to fight her and free the princess even tried to be nice to her, let alone flatter and woo her. Donkey was probably her first and only shot at true love, and he was suddenly gone, apparently forever.
Fiona's transformation. By day, one form, by night another. And when Shrek kisses her, she murmurs that she's "supposed to be beautiful," to which Shrek says she is beautiful. Think about it - a pretty human probably wouldn't turn an ogre's head, but Fiona as an ogress? Smoking hot by Shrek's standards! Plus, she's more comfortable in her skin as an ogress than she is a princess, and being comfortable with one's self is always a turn on.
Exact Words are in play here because the curse will be lifted "by true love's kiss, and then take true love's form"
And foreshadowed, when he talks about the sunflower. He doesn't like it, but since Fiona is "pretty", she might. He thinks Fiona is unattractive, and says so!
He doesn't say that she is unattractive, he actually does state that she is pretty. He seems more like he is stumbling on his words as he has never felt this way before and doesn't know how to confess his feelings.
In Shrek, it is only after the scene with the arrow in his butt does Shrek start to slowly fall for Fiona; so, the arrow is a symbolic Cupid's Arrow.
Farquaad chose Shrek's swamp for his Fantastic Ghetto because he knew there was an ogre there and decided it's easier to move every other fairy tale creature to his place rather than taking pains to move him anywhere else.
This may double as Fridge Horror: He is literally sending all of the annoying cartoony animals to live with a sociopathic Ogre that is well known for butchering people. He may have just been hoping Shrek would eat/kill/maim them all!
The only characters in the series who have Disney-style in-universe musical numbers, as opposed to scenes set to popular real-life songs, are Fairy Godmother (Shrek 2) and Prince Charming (Shrek the Third), and both of them actually do a stage-setting for those numbers (Fairy Godmother with magic, Prince Charming the old-fashioned way). And of course it makes sense as both a Deconstruction of Disney musical numbers, showing the need for stage-setting, and a Take That!, considering that both characters are villains.
Similar to my moment of Fridge Brilliance for Disney's Robin Hood, this occurred to me recently. It may be surprising for viewers that Robin Hood in Shrek is apparently French, since he comes from English folklore. However, during the historical period in which Robin Hood would have existed, England was ruled by the French Plantagenet dynasty.
However, to this Troper, this might be a case of Critical Research Failure, as in the original Robin Hood tale, robin hood was a Saxon who was resisting the Norman (aka French) rulers.
Also William Fitzooth, Robert's father, was of born Norman and Saxon parentage so it isn't like French would have been unknown to Robin.
The first movie has a joke where the smell of brimstone is blamed upon Shrek, to which Shrek tells him, "If it was me, you'd be dead." This just seems like hyperbole at first, until you remember the beginning of the movie where Shrek did kill a fish with his fart...
He didn't exactly kill it. When he was getting out of the water, he grabbed the fish and it freaked out like any fish would if it was being take out of the water. So maybe Shrek's fart temporarily stunned the fish until Shrek grabbed it. Just a thought.
It is most likely that the fish (as well as the other two behind Shrek) are dead, given that living fish don't float to the surface like that as fish have an organ that regulates their buoyancy.
In the Shrek novel by J.E Bright, it says the fish aren't dead, they just floated up because they didn't want to keep smelling the flatulence
Lord Farquaad's famous "sacrifice" line does at least make sense if one only looks at the words. They are his soldiers, and judging by how they've won the competition, some of his best, so if they die, he had technically sacrificed them.
Donkey getting distracted by the "onions have layers" with parfaits actually makes more sense with what Shrek was trying to say. If you peel back an onion's layers, you get the same thing; more onion. In a parfait, there's a new flavor in every layer, like a new layer under Shrek's seemingly distant personality.