This is probably a stupid beginners question but I would like to find a way - using my beloved sitespinner - to adapt my pages so that they look 'full screen' on different screenresolutions. any tips ?

Have you tried horizontal page centering? -- Page Editor > Special Effects.

no, but I will. Thanks for the tip - I will see how it goes.

Also, see the FAQ on the different page layout options here.

After checking Derry's thread I've got curious how to actually create a site that is top-left justified where components expand and contract to the resolution/browser settings. The first part is no problem, it's tha latter part I would like how to do.

There is a tutorial on Page Centering and Sizing -- see Help > Tutorials.