All you have to do is select the video and hit the delte button on your keyboard.
Also if you don't want the video to go on your iPod you don't have to delete it from iTunes. Just select the manual syncing option in iTunes. Make a playlist of the videos you want on your iPod and then just drag and drop that playlist onto the iPod. It's pretty simple
I have videos on my ITunes that I would not like to download onto my IPod because it will take up too much space. When I right click the video it does not say clear and I do not know how to delete it. This is on the newest version of the ITunes.

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