Even though the prices of the DVD9 discs (the ones holding the full 8.5GB of data) have become cheaper and cheaper, it still makes more sense to compress your data and / or remove unwanted features and use a DVD5 (the ones labeled as 4.7GB) in order to backup your favorite movies, as the price per disc is cheaper, your burner can burn them in higher speeds and they are most widely supported by standalone players. Also, you probably won’t need that extra languages, making of and commentary tracks of the original DVD.
