If you are going with a fixed layout then you should not use % at all. Size you image to the actual px values you want it to appear in. That is the main advantage of fixed widths, you specify every think in actual px values so that no matter what resolution the page is viewed under it will always look pretty much the same (just with more space either side of the page).
Don't use max-height etc. just set the height/width so the image does not stretch the template.
HTH,
JC
below is the code from reset-fonts.css, one of the files included in the link you recommended to me.
if the width is "em", if my research serves me correctly that means the width is dependent on the text size. if i dont have text, i use the image instead, do i want to change this setting to a "px" dimension?
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Copyright (c) 2008, Yahoo! Inc. All rights reserved.
Code licensed under the BSD License:
http://developer.yahoo.net/yui/license.txt
version: 2.5.1
*/
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