How to resize my wordpress site

maybe width900px?maybe 860px? i realy have no idea,in my wordpress i set width=960px,.
en,there is some themes can resize with browser size automatic.

This thread looks closest to my question. Searching documentation has not helped me. We have WordPress 2.04 as an add-on from Earthlink which hosts our web site. Recently have activated it and want to center and limit the page width of the basic kubrick template. It looks fine on a small monitor but is elastic so spreads full width on a large monitor. How and where do I find the place(s) to change this on the stylesheet and other locations (which files) if needed?

Is there a best suggested size

If you want the site to work as effectively as possible across a range of screen sizes, set the page or wrapper width in percentages rather than using pixels. Something like:
#wrapper {width:96%;margin:0 auto;padding:0;}

Also consider setting a max-width on your main page/post area as lines of text become difficult to read if they extend much beyond 1000px:

.post {max-width:1000px;}

Don’t bother specifying height unless you’re using a highly graphic-intensive theme and are happy to literally edit your posts, pages and/or excerpts to “fit” specific areas.

@lscarth: Are you sure you’re using Kubrick? That theme is fixed-width. Or at least the current version is. And all of the older versions I’ve seen. Could you be using the Classic theme? That is a full-width design but it could be easily modified to to restrict it’s max width.