I have a huge collection of DVD movies and video files. And I always put a few movies on my iPod to kill time while travelling.
DVD movies cannot be transferred to iPod via iTunes, so I had to find a converter to do that. I have used a few converters and the one I am using now is video to MP4 for iPod http://www.welldownload.com/rip-dvd-to-video.html . It is not free, but not expensive either. I decided to spend the money coz it does a good job on the final quality and conversion speed. And if I don't want to put a whole movie, I can just convert part of a movie onto my iPod with this app.
Most of my video files are not MP4 formats that can be directly used on iPod, so I also bought the  DVD to iPod Converter for Mac at http://www.welldownload.com/rip-dvd-to-ipod.html  from the same company coz I thought it would also be nice app, and it turned out to be so :) Actually, this video converter and the DVD converter are pretty much the same as far as the functions and the operational steps are concerned, and the only difference to me is that one is to convert DVDs and the other is to convert video files. If you also want a video to iPod converter, you can just download a trial version to see if it is what you need.

How to convert DVD and video to iPhone, iPod touch/classic/video/nano, Zune, PSP, etc

Part 1:Convert DVD movie to iPhone, iPod touch/classic/video/nano, Zune, PSP, etc
Part 2:Convert AVI, WMV, MPEG, RM, RMVB, ASF, MOV, DivX, XviD, MPG, etc to iPhone, iPod touch/classic/video/nano, Zune, PSP, etc
It is easy-to-use and the converting speed is fast! After testing, all formats conversions work well, the output audio and image quality is excellent! Let's view the steps.
Part 1: Convert DVD movie to iPhone, iPod touch/classic/video/nano, Zune, PSP, etc
1.Download the latest version Ultimate DVD Video Converter Suite at http://www.welldownload.com/convert-DVD-video-to-iPhone-iPod-Zune-PSP.html and install it.

2. Run the Ultimate DVD Converter, load your DVD by clicking 'Open DVD' button or choosing 'Open DVD' from 'File' drop down menu. One or several titles appear in the list after loading DVD.

3. Profile select. You can choose all video formats: iPod, iPhone, iPod touch, iPod video nano, Zune, PSP, video capable MP3 players, video capable mobile phones, Pocket P.C and so on. iPod MPEG4 Movie(.mp4) is the default DVD for iPod video quality. Set the appropriate format as you like.

4. Output settings. Set your Audio/Video output Settings and tick appropriate parameters.

5. Choose the pathname where you want to save your video files by clicking the right button of Output table. When everything is setted well, click the 'Convert' button to start converting.

Tips:
Tip1: Crop---- Choose the crop mode
Tip2: Resize-------Choose the output size you need
Set Crop to "Crop both black bands" and resize to be "stretch to full screen" if you don't need to keep the subtitle.
Set crop to "Crop the upper black band" so you can keep the subtitle in the down black band.

Tip3: Mode
Direct mode, you can convert the main movie directly.
Batch mode, you can choose the chapter you need to convert.
Part 2: Convert AVI, WMV, MPEG, RM, RMVB, ASF, MOV, DivX, XviD, MPG, etc to iPhone, iPod touch/classic/video/nano, Zune, PSP, etc
1.Download the latest version Ultimate DVD Video Converter Suite at http://www.welldownload.com/convert-DVD-video-to-iPhone-iPod-Zune-PSP.html and install it.

2. Run the Ultimate Video Converter, load the video files you'd like to convert by clicking 'Open file' button.

3. Profile select. You can choose all video formats: iPod, iPhone, iPod touch, iPod video nano, Zune, PSP, video capable MP3 players, video capable mobile phones, Pocket P.C and so on. iPod MPEG4 Movie(.mp4) is the default DVD for iPod video quality. Set the appropriate format as you like.
4. Output settings. Set your Audio/Video output Settings and tick appropriate parameters.
5. Choose the pathname where you want to save your video files by clicking the right button of Output table. When everything is setted well, click the 'Convert' button to start converting.

Tips:
Tip1: Crop---- Choose the crop mode
Tip2: Resize-------Choose the output size you need
Set Crop to "Crop both black bands" and resize to be "stretch to full screen" if you don't need to keep the subtitle.
Set crop to "Crop the upper black band" so you can keep the subtitle in the down black band.
Tip3: Mode
Direct mode, you can convert the main movie directly.
Batch mode, you can choose the chapter you need to convert.

Detail information at http://www.welldownload.com/convert-DVD-video-to-iPhone-iPod-Zune-PSP.html

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