Villainous Gru lives up to his reputation as a despicable, deplorable and downright unlikable guy when he hatches a plan to steal the moon from the sky. But he has a tough time staying on task after three orphans land in his care.
The woman who runs the orphanage neglects and abuses the children (eg. making them stay in a cardboard "box of shame" as punishment). Also, we see in flashbacks that Gru's mother was (and still is) verbally abusive to him; apparently this influenced him to become a villain.
Sort of. Gru and his verbally abusive mother seem to be on relatively good terms and she acknowledges that he is a better parent than her by the end of the movie
Gru hits the monster "dog" against walls etc while trying to get it to stop biting him. A shark is punched in the face. Squid and piranhas are shot out of guns as weapons.
A little girl holds her breath and turns red during a tantrum. She falls over as if she passed out from lack of air, but we see her acting normal again a second later.
A child’s toy gets disintegrated, but she gets a replacement eventually, made from items from a store not meant for that, and then later another replacement that is more child-appropriate.
There are three orphan girls who are main characters in the film. Their situation is sad (they live in a lonely, cruel orphanage at the start) but we never learn anything about who their parents were or what happened to them, so the loss of their parents isn't a big focus.
One of the minions (male voiced with masculine names) dresses as a woman to pass as a human family, but it's not revealed comedically or addressed by any of the characters. The main character is later shown dressed like a girl as a child and laughed at.
Gru's mother shows a photo album to the young girls, including a picture of Gru as a child with long hair and "feminine" clothing. They agree that he "looks like a girl" and laugh at him.
Near the beginning, the TV news shows guns being fired. Those are the only realistic guns, but throughout the film there's violence from gun-like weapons, like cannons/missile launchers, a gun that freezes its target in ice, and guns that fire squid or piranhas.
There is a possibly frightening moment when a little girl goes inside a box lined with spikes; the door is shut and a pool of red liquid leaks out from under the door. A moment later it's revealed that one of the spikes punctured her juice box and she is unhurt.