If you want to search for an article in a specific category eg. News or Sport, click on the links at the top to list the relevant articles, and search from there. eg. If you are searching for a sport article, click on the sport link to show all sport articles, and then use the search function.
Click on the button to open the wallpaper you want. Right-click on the wallpaper and choose 'Save As'. To set the image as your wallpaper, right-click on your desktop, choose Properties, go to Desktop and 'Browse' to the location of the file. Choose the image and click on OK.