Orion Pictues doesn't even exist any more. It died shorty after the release of the Weird Al film, UHF. Orion was in serious financial trouble, and they thought UHF would save the company. Sadly, UHF opened the same weekend as Batman, and Honey I Shrunk the Kids and it couldn't compete with those big movies, so it flopped at the box office. This was the nail in the coffin for Orion Pictures. I don't know what happened after that, but perhaps MGM picked up some of Orion's films, like Robocop. I do know that the recent DVD release of UHF was done by MGM, so like I said, they either owned part of Orion, or picked up rights to the films after it went under.
While Orion was around, it wasn't Disney's. No, MGM is not owned by Disney, they just have a partnership for the Disney-MGM Studios park, giving Disney the rights to make rides from MGM movies.
