DVD ripping software, the movie/TV show you wish to edit on DVD and Editing software.
In some cases, people actually take it up a notch by using 3-D modeling software for older TV shows that used model effects. An example can be seen in this clip from the original "Battlestar Galactica", where we see a shot of the Vipers and Shuttle landing on Kobol (which previously was not included). Some even use Adobe After Effects to enhance scenes that they feel should have used some sort of effect.
The special edition dvd of Memento has a easter egg that allows you to view the film in chronological order (with Teddy getting shot at the end and shown forward instead of in reverse). The film ends with the Polaroid of Teddy shot developing while the opening credits role.
Basically all the black and white parts play first- followed by all the colour parts in correct order.
I've been seriously considering taking the Bluray release of the OT when it comes out and re-cutting it to be as close to the original releases as possible. It's the closest I'll ever get to the originals in HD...
I forgot, I was also curious to see if I could takes episodes of "Smallville", remove Clark and make a Green Arrow show. Particularly the the flashback of his origin, the Toyman episodes and "Roulette".