Alot!
No, owls cannot talk. Even in Harry Potter.
Janet Frame
Elmo is one of the snowy owls who played Hedwig, I knew the mother owl, Kurgan, who was in a Coke advert
mostly because snowies are among the larger and more powerful owls and it would be very difficult for a Great Horned to hunt one. Great horned owls are sort of famous for being 'cannibals' and eating other owls, but Snowy owls are quite large for owls, and they are in fact larger than Great Horned owls. when hunting for food, owls usually wont try to attack anything larger than themselves.
Owls in general are famous for this ability.
Paul Klee.
No Butterfly owls are acutally Butterflies. And Spectacled owls are real owls.
No, the biggest owls in the world are The Eurasian Eagle Owls.
No, there are also eagle owls, tawny owls, and more.
Smaller owls, such as Burrowing Owls and Screech Owls, do eat insects on occasion.
Great Horned owls, barred owls, eastern screech owls, northern saw-whet owls, barn owls,short eard owls and long eared owls.