Technically, there have been, at one time or another, 8 possible endings to the film, all of which are included, in way, shape or form, on the DVD.
1. 'Jim Dreams and Dies': The original scripted ending (which is not the ending that exists in the finished film) involved an extension of the hospital scene after Jim, Selena, and Hannah have escaped the mansion. In this version, the scenes of Selena working on Jim are much longer, and are intercut with a kind of impressionistic 'flashback' to the accident which put Jim in hospital prior to the opening of the movie. After doing everything they can to save Jim's life, Selena and Hannah eventually realize that he is gone, and they despondently leave the hospital together. This ending was shot and edited, and was the original planned ending for the film, but initial test audiences responded negatively, prompting director Danny Boyle to conclude that because the film was so bleak and had asked so much of the audience prior to the dénouement, to end it on such a low note was simply too harsh. Boyle was also worried because he felt the audience misinterpreted the final shot (Selena and Hannah walking out of the hospital, with the doors swinging closed behind them), and he didn't like this level of ambiguity. Specifically, Boyle and scriptwriter Alex Garland had always intended the last shot to signify that Selena and Hannah were going to survive no matter what happened, but test audiences took it to imply they were heading off to certain death. This ending can be found on the DVD in the deleted scenes, under the title 'Hospital Dream'.
2. 'Jim Dies': The same as above, but without the flashback scenes. This was the ending found at the end of the credits on American prints of the movie and when it was played on Sky Movies in the UK.
3. 'Rescue Coda': The theatrical ending with Jim surviving the gunshot wound and he, Selena and Hannah hiding out in the mountain district until they are found and rescued. This is the version with which the theatrical release and the DVD release end.
4. 'Rescue Coda without Jim': A combination of the 'Jim Dies' ending and the 'Rescue Coda' ending. Jim dies in the hospital, but rather than the film end with Selena and Hannah leaving, it cuts to the cottage and the rescue scene simply plays out without Jim. This can be found on the DVD in the Alternate Endings under the title 'Alternate Ending'.
5. 'Escape Ending': During shooting of the film, for a period of time, Boyle planned to end the movie with the shot of the car driving away from the mansion after Mailer (Marvin Campbell) has dragged Major West through the back window. This was because the production had run out of money, and simply couldn't afford to shoot anything else (the film was shot almost entirely in sequence). After the Fox executives saw the movie with this ending however, they agreed to provide more money to shoot both the 'Jim Dies' endings and the 'Rescue Coda' endings.
6. 'Freeze-Frame Ending': Boyle briefly toyed with ending the movie on the freeze-frame as the taxi slams through the gates of the mansion. Fox didn't like that ending, so they gave Boyle extra money to shot the ending in the Lake District.
7. 'Radical Alternative Ending': This ending was never shot, but it was storyboarded. See here for details. It can be found as a series of animated storyboards in the Alternate Endings on the DVD narrated by Danny Boyle and Alex Garland.
8. 'Alternate Theatrical Ending': This version is similar to the 'Jim Dreams and Dies' ending, but with some minor differences; before they drive through the gate, as Jim is lying on the backseat of the car, he tells Selena that he saw a plane through the trees, thus giving her hope for the future. This ending is included on the Blu-ray disc.