yes, just set up different id's for your backgrounds then n your code ensure you pull through the appropriate id into the body tag
ie.
Code:
body { background-color: #fff;}
body #bluebackgroundwithfunckystripes {background-image: url('bluebackgroundwithfunckystripes.gif')}
body #pinkpolkadotbackground {background-image: url('pinkpolkadotbackground.gif')}
page 1:
<html>
<head></head>
<body id="bluebackgroundwithfunckystripes">
</body>
</html>
page 2:
<html>
<head></head>
<body id="pinkpolkadotbackground">
</body>
</html>
something like that