A Python script is available for free that assists in adjusting Mencoder settings for DVDs.
To make my life even easier, I've started using DVDInfo. This software finds the longest track on the DVD and displays subtitle track and audio information about it. This information is incredibly useful because it can be used to set the correct Mencoder options. If the DVD device is not specified, DVDInfo uses /dev/dvd as the default. However, I can also use a DVD image as the device, which is incredibly helpful when I want to watch a DVD without actually having the disc.
DVDInfo also has a feature that determines the title with the largest number of titles, and that title is considered the 'longest title.' This is typically the feature film on the majority of the DVDs I watch. However, if I want to display information on a specific title, I can simply pass the title number with the --title option. Overall, DVDInfo has been a game-changer for me, and I highly recommend it to anyone who watches a lot of DVDs.
Version 1.1: N/A