Hey Klaas,
I think you should try to design your site with css (using divs) instead of using tables. Tables are very confussing since you have to set attributes (cellpadding and cellspacing) to ech individual cell and you have to create a lot of useless cells just to keep your content aligned properly. In css you can create a div for each section of your site and the simply position it and set padding/margin on a master document (the stylesheet).
Some css pages that I have found useful are:
http://www.subcide.com/tutorials/csslayout/ http://www.wpdfd.com/editorial/basics/