Download and install one of the programs that are available to convert videos to the MP4 format. All of these programs work in the same manner, so it does not matter which program you choose.
Open the program you downloaded and click on either the "Add Files" or "+" button. Select the movie you want to convert from its location on your computer and click "OK."
Click on the "Profile" or "Format" button on the main video converter window and click the "MPEG-4" option.
Click the "Output Directory" browser button and select a place to save the new MP4 video file. Click "OK" to verify your location selection.
Click the "Start" or "Start Converting" button to begin the conversion process. Once the video has been converted, you can add it to your PSP using the Video Vault PSP software.