Technique I picked up recently for "cropping" images that are just slightly too big on a page. All you need to do this is some basic knowledge of HTML and CSS.
First, set up your image on the page in a div with a nice class or id for cropping.
The width and height will set up the size of your cropping box, and then the overflow line makes everything outside the box disappear.
Of course, right now, the box only crops from the upper-left corner of your image, which might not be what you want. To fix that, we need a little more CSS.