Adding Folders to the Gallery or Removing Folders From the Gallery
One of the first things you'll want to do is tell Windows Photo Gallery what folders to include. By default, your Photos folder is included, but you might want to add more. This is a simple process.

From the File menu, select Include a Folder in the Gallery. Browse to the location of the folder you'd like to add and click ok. Windows Live Photo Gallery will now include that folder. It will appear in the Navigation Pane under the All Photos and Video node.
If you have included a folder that you do not wish to be in the gallery, you can easily remove it. Go to the folder in the navigation pane that you wish to remove, and right click on it. Then select Remove From Gallery. This is the safe and preferred method of removing a folder from the Gallery. Do not delete the folder with the intention of "deleting from the Photo Gallery" -- it will delete it on disk. Instead right click and Remove it.
Next: Importing Photos from a Digital Camera, Memory Card, or CD/DVD.