The wallpapers are available in 3 different sizes per image. Right-click the desired link and select "save as" to download! Dimensions are given in 'pixels' and refer to picture sizes to suit most common screen sizes.
To then use the image on the desktop, right-click an empty area of ??your desktop and select Properties. A box will appear called Display Properties (Screen Properties). Choose Desktop, and then Background. Can not find Nanne where Scroll to where you saved her, and then click. Finish with OK. Note that this description applies to PCs with Windows 2000, or more modern. Macs and older Windows works a little differently.