Download the New Xbox 360 Dashboard Without Xbox Live

This article will show you how to download the new version of Dashboard without having Xbox Live.

Steps

Decide whether you would like to burn a CD/DVD or use a USB flash drive. (The flash drive is easier, faster, and rewritable.)
Go to this site and scroll down until you get to the bit which says To create a DVD or CD. Click the download link. Make sure you don't change the file name when you save it.
Right click on the zipped folder and click Extract all once it is successfully downloaded. Then copy the extracted file onto a flash drive, or burn a CD.
Turn on your Xbox 360 console and plug in the flash drive or insert the CD. There should be a box that should ask if you want to update. Choose the yes option.
Watch the intro video play once it has been updated.
Enjoy the new Dashboard. More options can be found by pressing the Guide button on your controller.

You can also download the backwards compatibility updates, which will allow you to play the most current list of backwards compatible Xbox games.
Make sure you keep the download file name the same when you save it, otherwise the update will not work properly.

The new Dashboard is really meant for Live. All of the channels except for My Xbox will have nothing in them as they all get their content from Xbox Live.
You will not be able to create an avatar unless you are on Xbox Live.