If you should happen to rename the iDVD project file, be sure to keep the .dvdproj extension; if you don't, iDVD won't recognize the file, and the Finder displays it as a folder.
iDVD 5 offers a new feature, OneStep DVD, that automatically imports video from a camcorder and burns it to a DVD disc. This is good if you need a plain DVD copy of your footage, but it won't give you a menu or interface of any kindthe video just begins to play immediately after you insert the disc into a DVD player. Since we're creating a DVD with menus and other elements, we don't need to use OneStep DVD.
The iDVD Interface p. 72
You cannot resize the iDVD window.
In the Map view, clicking the triangles on each menu icon hides objects farther down in the hierarchy. This is useful if you're navigating a complicated project and don't need to see all of the branches on screen at once. Clicking the triangle again reveals objects that were hidden.
iDVD uses a lot of your computer's processing power to display motion elements, so unless you're actively working on motion (or you have a wicked-fast Power Mac G5), I recommend turning Motion off while editing your iDVD menus.