I dont know if this has been covered already in the forums but from what topics I've read it seems a lot of people are finding it difficult to organise their videos within the set 'Music Videos' 'Movies' etc on their Zune. Also everyones using a mix of programs to edit tags (tigotago, wmattributeeditor, zmeta etc). No problem but bear in mind that I use TigoTago so things might be slightly different from what I've written here, in terms of where you find each tag to edit.
So far TigoTago is the easiest to get access to all they ID keys along with video descriptions etc.
Grab the app from here...
http://tigotago.com/download.htmlBasically the Zune uses 'MetaData' to categorise your media. Every file you sync has a tag(s) which tells the zune which folder it should be displayed in. The idea is to change these tags yourself so you can decide where each file appears on your Zune device.
The question most people are asking is "What do I change the tags to???" Read on...(Note: Some of the tags will be already correct, like the primary tags that define type of media, most likely you will only need to change the secondary tags but they are all here anyways...)
For MUSIC Files:Edit the meta data for your chosen file(s) and change the
WM/MediaClassPrimaryID tag (located under the 'Media' heading) to
D1607DBC-E323-4BE2-86A1-48A42A28441E(Note: 99% of the time this will be correct...and bear in mind this value is for MUSIC AUDIO ONLY, audio that is not music has another tag, see below.)
You
do not need to change the WM/MediaSecondary tag.
For VIDEO Files:First off, you have to define ALL video content as video, to do this change the
WM/MediaClassPrimaryID tag (also located under the 'Media' heading) on your chosen file(s) to
DB9830BD-3AB3-4FAB-8A37-1A995F7FF74BNow, you have to change the
WM/MediaSecondaryID tag in order to specify what type of video it is, so change the tag to one of the following:
For Movies -
A9B87FC9-BD47-4BF0-AC4F-655B89F7D868For Music Videos -
E3E689E2-BA8C-4330-96DF-A0EEEFFA6876For TV Shows -
BA7F258A-62F7-47A9-B21F-4651C42A000EExample: (The correct values for me setting the video to 'Music Video'
For NON-MUSIC AUDIO (spoken word recording etc):Now i don't know whether the Zune would use this tag or if it seperates non-music audio but here is the
WM/MediaPrimaryID tag for other types of audio:
01CD0F29-DA4E-4157-897B-6275D50C4F11----------------------------------------------------------------------
*UPDATE*I decide to start messing about with various tags on my new video release (blatant plug -
http://www.wesweatblood.co.uk/wsb3street.html 
) and discovered the corresponding tags to edit the Directors and Descriptions for video files. Some of you probably figured it out already but for those who havn't...
The tags you need to edit to change the Artist/Director of the video are the
WM_AlbumArtist and the
WM_OriginalArtist tags under the 'Misc' heading. Just enter whatever you want the artist/director to appear as on your Zune.
(Note: the bug with music videos showing "unknown artist: 2006" has not been fixed so it will still show that in the list of videos, however once M$ gets around to fixing this, they will appear.

To add a description that will appear on the Zune when you choose the video from the list, you need to edit the
WM_SubTitleDescription tag under the 'Video' heading.
Just add whatever you want to describe the video.
Example: (Me adding my description for Bowling For Soup's 'London Bridge' cover video)

Make sure you save these values, as TigoTago requires you to manually save the data before it is applied.
That's it. Now as long as you have put the right tag in the right place (!) all your videos should now be organised properly. Once you've re-sync'd them to your Zune obviously (though I did read somewhere that you might have to delete them if they are already on the Zunee before you re-sync and the new data is used.)
Any questions? (Any categories I've missed or anything...?)
Hope this helps the people who are having problems...
Bii

EDIT: For a bit of reading, i used the MSDN library for the tags and other info....
http://msdn2.microsoft.com/en-us/library/ms867702.aspx-----------------------------------------------------------------------------
(Tried to add this to my Sig, but not enough space...)
My Current Guides:Guide to Editing WindowsMediaMetaData. Organise Your Videos Properly -
http://www.zunescene.com/forums/index.php?topic=4232.0Get Free Music Videos, Live Performances & Exclusive Interviews From Your Favourite Artists In Zune Playable WMVs. No Convert Required! -
http://www.zunescene.com/forums/index.php?topic=7375.0Rip DVDs/Convert IFO Files Directly to Zune Playable WMVs -
http://www.zunescene.com/forums/index.php?topic=7383.0Convert AVI/MPG/VOB Directly To Zune Playable WMVs (Encode360) -
http://www.zunescene.com/forums/index.php?topic=7489.0Convert Incompatible WMVs to Zune Playable WMVs (WMencoder 9) -
http://www.zunescene.com/forums/index.php?topic=7493.0