Directions for wallpaper:
Click the size image link you want that is relative to your screen size, after the picture has opened fully click on the image with your right mouse button and then choose "Set as background".
Your default background settings may have be set to "Stretch" which will stretch some of these images out of shape, so you will need to change it to "Center".  To do this on a Microsoft Windows PC, right click an empty area on your desktop, choose Properties, select the Desktop tab and then change the Position to Center. 

Larry Waimon's "Rolling Tribute"

800 x 600	1024 x 768	1280 x 1024
251kb	443kb	548kb

Toasty's Burnout

800x600	1024x768	1280x1024
90k	137k	223k

Mount Hotham Australia

800x600	1024x768	1280x1024
113k	160k	238k

Eric Godwin's Serious Custom

800 x 600	1024 x 768	1280 x 1024
246kb	391kb	627kb