I take it that you have a DVD which has already been produced, and you want to loop a section of video on a DVD player or PC? You can do this in VLC media player. VideoLAN, Free streaming and multimedia solutions for all OS!.
- Download and install videolan
- Open up your disc and go to the start of the video you want to loop.
- Select Tools > Bookmarks and
- Click create.
- Go to the end of the video you want to loop and click create a second time.
- Now click view > advanced tools, and then click the third icon from the left to loop the video.
Most DVD players will also let you set an in an output to loop.