The bike belonged to Sirius Black. Hagrid met him outside the Potter's house and Sirius gave Hagrid the bike to transport Harry, saying he wouldn't need it anymore as he knew he would be blamed for Lily and James death.
Sirius Black gave Hagrid the flying motorcycle. Hagrid used it to get Harry to 4 Privet Drive after his parents were murdered by Lord Voldemort (Known as You-Know-Who or He-Who-Must- Not-Be-Named).
The bike belonged to Sirius Black. He gave it to Rubeus Hagrid to transport Harry to the Dursleys.
Rubeus Hagrid is seen driving the flying motorcycle in the first and last books. It previously belonged to Sirius Black, who gave it to Hagrid on the night Lily and James were killed.
thestrals
Hedwig is the only one i know of.
You go through parts of the books as if you're flying with Harry, Ron, and Hermoine.
You need Harry because he is the only one who can use a wand while flying and use the orange spell to blow them up.
Harry Potter wasn't really dreaming, he was actually seeing something that was really happening. He saw a muggle called Frank Bryce check on the house that he was paid to maintain and being murdered by someone (that turned out to be Voldemort). Frank (and therefore Harry) overheard voices (Voldemort, Barty Crouch Jr and Peter Pettigrew) planning to murder someone.
Apparation/Disapparation, riding on a dragon, riding on Sirius' motorcycle, walking, running and flying.
Rubeus Hagrid delivered Harry Potter after picking him up from Godric's Hollow. He was asked to do so by Albus Dumbledore.
Flying
Sirius Black was briefly mentioned in Harry Potter and the Sorcerer's Stone when Hagrid tells Dumbledore how he took Harry from Sirius and borrowed his flying motorcycle, but he does not become a prominent character in the series until the third book, Harry Potter and the Prisoner of Azkaban.
during the 7th harry potter book when hagrid and harry are traveling to the burrow hagrid presses this button that makes the flying motorcycle spin and the firebolt, Hedwig, and other things of harry fall to the ground. (harry is able to catch Hedwig's cage but not before it is hitting by a curse, in result killing Hedwig)
Hagrid
thestrals
There aren't going to be any more Harry Potter movies, so no.
It didn't necessarily tell him anything about his life with the Dursley's. But if it had, it would have told him about the magical background that he was born into, since this dream takes place on a flying motorcycle.
the awesomeness of the story line and how great the story was written
The dangerous flying game in Harry Potter is spelled Quidditch.
Hedwig is the only one i know of.