Screen capture is ok if you want to capture a portion or even all of what you see on your screen, but if you want to capture a Web page that requires scrolling, PDFmyURL.com is the quick and easy answer. You can read about it on Profhacker in The Chronicle. Update 10/20/10: Apparently faculty on campus can get through the block, but that would not apply to staff or students.
So let’s say you need a static image of a long page, for a handout on those occasions when technology is not available–in a meeting, perhaps. PDFMyURL captures the page in an instant, preserving the formatting of the page, unlike what happens when you just try to print it out.