A great extension to capture a screenshot of your current web browser is FULL PAGE SCREEN CAPTURE. Once you install the extension, simply click on the icon and the extension will take a screenshot of your web browser. You can then click Ctrl S to save the image or drag the image to your desktop.
Click on the link above to go directly to the Chrome Web Store and install the free extension. Give it a try. Taking a screenshot of open web pages has never been easier.