Point your computer's browser to a website which allows you to watch Dragon Ball Z online (see Resources).
Select the episode you want to watch. Click the episode number to load it.
Click the red "Play" button in the middle of the video window to watch your chosen episode.
Buy or rent DVDs of the original Dragon Ball Z series. These are available in box sets organized by seasons or series (see Resources for the complete series).
Select the DVD containing the episodes you wish to watch. The DVD packaging gives a brief synopsis of each episode.
Insert the disc into your DVD player or computer DVD drive and wait for the disc's menu screen to be displayed.
Choose "Episodes."
Pick the episode you wish to watch. Select "Play All" from the disc's main menu if you want to watch all episodes in their original order.