One thing that you might be failing to do is to reduce the DVD data rate, which is intended for display on a full size TV screen, and to do other things that will radically reduce the file size on your phone.
When ripping a DVD for use on a computer or similar device, you need to know the following:
- Whether the program aspect ratio is 4:3 or 16:9
- If it's 16:9, if it's on the disc in anamorphic format or letterboxed
- Whether or not the original source came from film
Although it may be possible to save the NTSC or PAL video in its native MPEG-2 format, that would be very wasteful for use on a mobile device with limited storage. At the very least you'd want to deinterlace the video so it displays properly on progressive scan devices.
- IMO the best practice is to first deinterlace the ripped MPEG-2 video to 480p or 576p. This is the time to apply reverse telecine to get back the original 24fps video if applicable.
- After that, convert the resolution and aspect ratio to match your particular device. 960x540 in this case. You may need to crop out the letterboxing parts, if any to save file space and make a 16:9 program display properly.
- If the audio is in surround sound, convert to plain stereo.
- Save the transport stream at a greatly reduced data rate, as low as 1Mbps for MPEG-2.
- If possible, convert to MPEG-4, which will allow a smaller file with no loss of quality. Data rates much less than 1Mbps are possible with the H.264 encoder.
You'll need to experiment with how small you can make the file without making it look awful. IME it's possible to squeeze a feature length film from a 9GiB DVD into a file much smaller than 1GiB with H.264.
Getting all of the software to do this easily is a whole 'nuther topic.