You no longer need to buy expensive software to resize and crop images. I've found a great online tool called Snipshot that does it free, and very easily. I'll show you how.
Go to the Snipshot website and click on the Choose File button.
Browse to the file you would like to modify and double-click it. Depending on the size of the image, it may take a few moments. Once it's finished loading, you will see this screen:
To Resize the image, click and drag any of the small red boxes around the image. The corners will resize all of it at once, the ones on the sides will resize horizontally or vertically. When you let go of the mouse button, the image will resample itself. The size you see will be the actual size of the image when done. Once you have it down to the size you want, click the Save button. Now, that image is ready to place on your website, document, or email.
To crop, click on the Crop button:
This will place a box in the middle of the image. The shaded area is the area which will be removed. You can resize this area by clicking and dragging on one of the red boxes. When the area is what you'd like, double-click on the inside of the box.
When you are finished cropping, click the Save button to re-save the new image.