Zune is a product line of portable media players manufactured by Microsoft. The line also includes Zune software and the Zune Marketplace services sold by Microsoft, which provide online music, video, and podcast downloads. Zune players come in two variants, one hard-drive based and the other flash-memory based. Both play music, videos, and podcasts, display images, and receive (but not record) FM radio. You can share files wirelessly with other Zunes and via USB with Xbox 360s and Windows PCs. Any Zune can also be synced wirelessly with a Windows PC.
 
The following guide will show you how to convert DVD to Zune compatible video/audio format so that you will be able to watch DVD movies on Zune, Zune HD. Let's take a look at video/audio formats Zune HD supports first:

Video Support:
WMV
MPEG-4 (MP4/M4V) (.mp4) Part 2 video
H.264 video
DVR-MS

Audio Support:
Windows Media? Audio Standard (WMA) (.wma)
WMA Lossless
Advanced Audio Coding (AAC) (.mp4, .m4a, .m4b, .mov): .m4a and .m4b files without FairPlay DRM
MP3 (.mp3)

The software you just need is Clone2Go DVD to Zune Converter. It is very easy to convert DVD to Zune video/audio format for Zune HD:

Step 1. Import DVD movies

 
Insert the DVD disc into the disc drive, click the "Open DVD" button to import it. Or if the DVD movie is saved as a folder on your computer, you need to click the "Add Video" button to locate that folder, which is composed of two separate folders: VIDEO_TS and AUDIO_TS. From the VIDEO_TS folder, select the .vob file to import and then click "OK".

Note 1: You can also use this DVD to Zune Converter to convert video files for your Zune HD. You just import videos stored on your PC by clicking the "Add Video" button and then click "OK". The supporting formats are shown as follows:

Audio Files (*.mp2;*.mp3;*.wav)
Windows Media Files (*.avi;*.wmv;*.asf;*.dvr-ms;*.ms-dvr)
MOV/MP4 Files (*.mov;*.mp4;*.3gp;*.m4v;*.qt)
Real Media Files (*.rm;*.rmvb)
Flash Video Files (*.flv)
MKV Video Files (*.mkv)
AviSyth Scripts (*.avs)
Other Video Files (*.mpq;*.dv;*.vob;*.m1v;*.m2v;*.dat;*.amv)

Note 2: You can also use this DVD to Zune Converter to download YouTube/Google videos for your Zune HD.

After the DVD movies have been imported, you can preview it on the main interface. You can also capture a part of the movie to convert, choose audio track and subtitle, customize video size, bitrate, audio bitrate, sample rate, etc before converting DVD to Zune HD.

Step 2. Choose output format

In the drop-down list of "Profile", navigate to "Zune" subcategory and choose the most appropriate profile as the output format.

 
Step 3. Start converting DVD to Zune HD and transferring DVD to Zune HD

Now you can click the "Start Encode" button to start converting DVD to Zune HD.

Note: The output files are easily available by clicking the "Folder" button on the interface.

After you get the output video files, you can now begin to transfer them to your Zune HD with the sync of Zune Software.

Extracted from http://www.clone2go.com/tutorials/convert-dvd-to-zune-hd.php