Please, keep in mind that usually DVD subtitles are just bitmaps (pictures), so it won't be very straightforward.

You basically have 2 options:

1. Use something like SubRip to extract the subtitles and convert them to SRT. Here's a nice guide on the subject: http://www.dvd-guides.com/content/view/231/59/ Then import the SRT into handbrake.
2. Download an SRT with the subtitles you want from someplace like opensubtitles.org and import the SRT into handbrake.

Please, keep in mind that usually DVD subtitles are just bitmaps (pictures), so it won't be very straightforward.

You basically have 2 options:

1. Use something like SubRip to extract the subtitles and convert them to SRT. Here's a nice guide on the subject: https://web.archive.org/web/20120224190445/http://www.dvd-guides.com/content/view/231/59/ Then import the SRT into handbrake.
2. Download an SRT with the subtitles you want from someplace like opensubtitles.org and import the SRT into handbrake.