I prefer to start by making a list of what I'd like to keep, with no regard for size. I try to prioritize each item so I can hopefully just start removing items from the bottom of the list until I have a small enough DVD to burn. Given that there are multiple titles which are several hundred Megabytes each, this approach may not work, but I'll cross that bridge when I get there. After playing the DVD and examining the various extras, here are my choices, in order of importance:
1. Deleted Scenes
2. Trailers for Once Upon A Time In Mexico
3. The Anti-Hero's Journey
4. The Good, The Bad, And The Bloody: Inside KNB FX
5. Ten Minute Flick School
6. Ten Minute Cooking School (Don't say anything unless you've eaten at my house!)
7. Film Is Dead: An Evening With Robert Rodriguez
8. Inside Troublemaker Studios
9. Other Trailers
10. Filmographies
11. DVD-ROM content
12. Soundtrack Information
The next step is to identify the items to be removed in DRM. Remember, the idea is to work from the bottom of the list, and to go no further than absolutely necessary. Fortunately, most titles have their own VTS, so it will just be a process of previewing the blocks in each VTS and then using Hide All Blocks to remove the entire VTS for each of those.
The first items you'll be removing, however, you won't find by just looking through the titles. That's because they're not titles - they're menus. Fortunately, all the menus are in the same VTS as the movie, so it will be fairly simple to find and remove them.
Expand VTS 3 and highlight Menus EN. Now you can preview each one (it works just like previewing titles) and right-click on the ones you don't want, using Hide Block to remove them. There are also several filler blocks that you can remove. After removing the Filmographies, DVD-ROM, Soundtrack, and filler menus, the disc is 7018.03MB.
Now you can start removing titles. After removing the trailers for other movies (VTS 11 - VTS 19) the disc is 6438.86MB. Removing Inside Troublemaker Studios (VTS 1) reduces it to 6092.96MB. Getting rid of Film Is Dead (VTS 6) drops the size to 5637.84MB, and removing Ten Minute Flick and Cooking Schools (VTS 9) gets it down to 5135.19MB. When you remove The Good, The Bad, and The Bloody (VTS 8) it will drop to 4483MB.
You've now hit the target size almost exactly. Notice that the Size listed at the top of the DVD Tree is now black instead of red. If, at this point, the project was just barely too big for a DVD-R, you could avoid removing anything else by hiding the menu transitions. Since motion menus are typically made up of at least 3 separate menus that play in order, and at least one of them is usually just a transition from one menu to another, you could remove the menu transitions, leaving the rest of the menus intact.
To do this, expand VTS 3, right-click on Menus en, and select Hide Menu Transitions. Even if you remove the same things I have, you might want to do this just to make the menus appear faster when you navigate between them. As you'll see in the next step, you can also remove just specific menus.