Rob Also in future posts for all who read this. When asking a question make sure you put in enough detail. This answer could be a little more specific if we knew more about what application is being used to make the animations. You can open the movie in it and export it using the settings for the DV codec. When you are creating movies in an application you need to specify that they are saved as quicktime DV compressed movies.
Quicktime movies can be many different types of movies.
When you go to render your animations in the future you should see if you can get to the settings for the quicktime compression. Save the movie as a DV and make sure your animation is the right pixel resolution. In the USA that would be 720x480 at 30 frames per second. When asking a question make sure you put in enough detail. This answer could be a little more specific if we knew more about what application is being used to make the animations.