Google Search allows the users to change the background image. This can be done using the Change background image link provided at the bottom of the page.
Open Google Search in a browser.
Click on the Change background image link provided at the bottom of the page.
If you are not already logged in to your Google Account, then you will be prompted to sign on to your account.
The Change background image, would display the following the windows using for selecting the background image. You can select the background image either from your computer, Picasa Web Photos, Public gallery or Editor’s picks. After choosing a background image, click the Select button.
Now your Google Search web page will be displayed with the background image.