Internet discussion would have sufficed for this type of question. As for your question, most websites are programmed so that the tables or what ever the web developer has used to create the layout, stretch to meet the size of your resolution. I.e, some websites will stretch width ways if you have a widescreen monitor etc. Although most stick to specific set sizes and don't get affected regardless of what resolution you use.
If you want to view the website smaller or larger (if it is one that stretches etc depending on your resolution), then change your resolution?
Breaks.