Hello Yolanda,
You will need two pieces of software, A. For ripping the content from the DVD B. Video editor.
You will want to use Handbrake to rip the content from your DVD, which is compatible with PC and Mac. You and find a guide here, on using the app to rip the family DVD.
Once you have a media file to work with you can head over to Komando.com to find a free video editor if you do not have something like Adobe Premier to edit your video.
Please come back and let us know how it went or if you have any more questions.