I thought I just explained that the minmum width of your table (with margins) is greater than 600px so that is the reason it won't fit into 600px or smaller. You can't have it fluid and also want a fixed width item inside. You would need to set a min-width to hold the layout intact but your min-width looks to be about 860px wide. Of course Ie doesn't understand min-width so you'd have to use one of the script/expression options if you went that route.
But the width from the "inhoud" DIV is set in % so when i view my site on a high res it still fills up my screen