how do i compress a dvd video file to around 700mb .avi?

Answer 1

You did not indicate how much you need to shrink the file. While you might be able to get it from 750-800 to 700 and still have a watchable quailty, anything more then that and the resulting picture will probably not be useable.

You would need a video editing software, such as Adobe Premiere. You can try it with Movie Maker, but its options are very limited.

You would need to open and resave the video with settings which will reduce the file size. Often converting from avi to wmv format will reduce the file size. You can lower the frane rate, lower the quality, or lower the screen size. Each will reduce the file size. But each will also reduce the quality of the picture. It will be blurrier, and may have some skipping, etc.