I also would suggest using a film like 1984 in excerpt form to help visualize the characters or the setting rather than showing the film. Show those excerpts at strategic points in the reading process that anticipate stumbling blocks to student understanding. The drawback to showing an entire film adaptation to struggling readers before introducing the novel might make them think they have "done" a book like 1984.
I would suggest taking short passages from 1984 that describe key elements (characters, setting) with a high level of descriptive detail and have students create storyboards that would translate those words into frame by frame images similar to seeing them in a movie. Have students work in groups allowing them to discuss the selected passage before working on an approach to the storyboard. You could then show how that passage was treated in the film and have students discuss their versions with the filmmaker's interpretation.