iDVD is a Macintosh application that was a part of the iLife suite that allows you to easily take media files and burn DVDs that are viewable in most normal DVD players. The program allows you to customize your DVD with various menus, some of which include motion and sound. iDVD is integrated to work with iMovie, iPhoto and iTunes. It was discontinued starting with OS X Lion.
To turn your media file into a DVD using iDVD, start by opening iDVD and giving the movie a name. You then will be brought to a screen like this...
Here you can choose which menu style you would like to use. By default the newest options will show up in the list on the right, just click on one of them to see it in the main frame. You should note that although there may be multiple "drop zones" in a given template you do not have to fill them all, and the words "drop zone" will not appear in the final product.
Once you have chosen your menu style you may then add your media. Click on the "media" button, which will bring up a different menu on the right side of the window. This window should look like this:
Your media files should be in the Movies folder, or a sub-folder there of. If they are not, use the Finder to drag the files into the Movies folder. To add your media files to the DVD menu simply clink and drag them into the desired position.
Once you have dragged them in you may change the name of the file within the program, or the title of the DVD. If you file will not work with iDVD you will most likely have to convert it to a supported file-type. To do this you can use the free-ware program FfmpegX.
It is also possible that the file is too long. DVDs cannot exceed 2 hours in length, if you need to cut down the size of your movie you may do so using iMovie.
When you are ready to burn, click on the little gray circle at the bottom of the main window, it will then turn into a black and white circle and begin to prepare your movie for burning.
Remember, you can only use iDVD if your computer can burn DVDs. Just because you have iDVD on your computer does not mean your computer has the capacity to burn DVDs! eMacs cannot burn DVDs, but most G5s and Mac Minis can. Also you will want to make sure you are using DVD-Rs. There are DVDs that are DVD+R, and these will not work in DVD-R burning drives unless the CD/DVD drive is DVD+/-RW compatible.