Hi Ryan,
I am not in a position to test right now, but yes, if you add 1px or 101% then you should always have a scroll bar (And that is a good point).
Positioning the footer
Because the wrapper is absolutely positioned its taken out of normal flow (as I am sure you will be aware) so to simply place this div below the wrapper will not work, it would simply ignore the #wrapper and be placed at the top of the viewport. Usually, when I use a full height wrapper that is positioned I would place my div inside the wrapper. Actually, its really important to do this and make sure the #footer is the last item inside the #wrapper. That wat the footer is alwasy at the bottom of the wrapper div and any content (text, images etc that is added inside the wrapper will also ensure the footer is pushed down. Just set whatever top margin you want on the footer to give you enough space between the actual page content.
Copy and paste this code and you can experiment for yourself.
THE XHTML
<!DOCTYPE html PUBLIC "-//W3C//DTD XHTML 1.0 Transitional//EN" "http://www.w3.org/TR/xhtml1/DTD/xhtml1-transitional.dtd">
<html xmlns="http://www.w3.org/1999/xhtml">
<head>
<meta http-equiv="Content-Type" content="text/html; charset=iso-8859-1" />
<title>Untitled Document</title>
<style type="text/css">
body {
margin: 0px;
padding: 0px;
}
html, body, #wrapper {
min-height: 100%;
height: 100%;
width: 100%;
}
html>body, html>body #wrapper {
height: auto;
}
#wrapper {
background: #CCC;
position: absolute;
margin: 1px;
}
#footer {
background: #7A96DF;
padding: 0px;
position: absolute;
bottom: 0px;
width: 100%;
margin-top: 0.4em;
}
</style>
</head>
<body>
<div id="wrapper">
<p>Your content placed here</p>
<div id="footer">information for the footer in here</div></div>
</body>
</html>
All said this is not perfect, some browsers such as safari may still render the footer below the content rather than at the bottom of the #wrapper, but it is a compromise solution and it still does not make the site unusable in any way.
If you really want full height and the footer to be at the bottom on all browsers, even old ones, then you may have to use a single table for your layout!
Hope that helps