To put just a color as your background: <body bgcolor="blue"> <style>body {background : Black; }</style>
To put an image as your background: <body background="HTTP://THE PICS URL.JPG"> <style>body{background:url(http://THE PICS URL.JPG) fixed}--></STYLE>
To have a two-color background: <style>body {background:#000000; filterrogidXImageTransform.Microsoft.Gradient(GradientType=1,StartColorStr=#000000,EndColorStr=#FFCC00); }</style>
To have a FIXED (it doesn't move) backgound: <body background="HTTP://THE PICS URL.JPG" bgproperties="fixed">
To let visitors change background color: <form name="BackgroundColor" method="post"> <input type="button" OnClick="document.bgColor='#COLOR'; "value="TEXT HERE"> <input type="button" OnClick="document.bgColor='#COLOR'; "value="TEXT HERE"> <input type="button" OnClick="document.bgColor='#COLOR'; "value="TEXT HERE"></form>
To have a flashy background: <a href="HTTP://URL GOES HERE.com"onmouseover="document.bgColor='aqua'; document.bgColor='yellow'; document.bgColor='orange'; document.bgColor='skyblue'; document.bgColor='coral'; document.bgColor='lightgreen'; document.bgColor='white'; document.bgColor='blueviolet'; document.bgColor='skyblue'; document.bgColor='hotpink'; document.bgColor='black'; document.bgColor='white'> TEXT GOES HERE</a>