I actually had this in mind as I was watching it in theaters. I hated the first 20 minutes or so. Just plain dull. But after the plane sequence, the film had me and I loved the rest of it. So maybe I'd just lop off most of those opening scenes.

- If the DVD doesn't come with an extended version, I would edit some of the deleted material back into the film, especially Superman's visit to Krypton and the Smallville scenes. Apparently, these were really needed to reinforce the film's theme of isolation and the world moving on w/o Superman.
- I'd edit most of the opening. The first scene with Lex is unnecessary. I'd try to cut down on his trip to the Fortress of Solitude, etc.
- I'd cut the young Clark flashback unless deleted scenes make it more important (the scene originally had young Clark finding the crystal for the first time, I think).
- Then I'd just trim a few of the film's excesses here and there.