Image Viewer has user friendly interface of three panels. On the Top left panel there is a Directory file tree. Beneath there is a file list of selected directory. All you have to do is to click the image name from the file list and the next moment you can view the image on the opposite panel.
When you hover your mouse over Image, you are ready to crop. Just draw\mark your selected area and Click on Crop button. This will show cropped image in new window where you can save the image in jpg\bmp\png format.