Robert -
More specifically, convert it to QuickTime DV-NTSC or QuickTime Apple Intermediate Codec depending on whether the video is 4:3 or 16:9. Use a corresponding Easy Setup in FCE before you import the converted video files/clips.
Note that while MPEG Streamclip is free, you may need to purchase the QuickTime MPEG2 Playback Component ($20, downloadable from the Apple Online Store) if you do not already have it on your Mac.
Also note that if it is a commercial or otherwise copyrighted/protected DVD, you are not licensed for any use other than private viewing, unaltered.