If you have a small JPEG or GIF file, you can resize the image using a free tool bundled with the Microsoft Windows operating system. Microsoft Paint is a small graphics program located in the accessory tools on the Windows start menu. One of Microsoft Paint's functions is image resizing. You can enlarge images or make them smaller using the resize tool. Once it's resized, you can save the new image to your hard drive for future use.
Right-click the image you want to enlarge and select "Open With."
Select "Microsoft Paint" from the list of applications. If you don't see Paint on the list, click the "Browse" button (in Vista, the button is labeled "Choose default program") and enter "C:\system32\mspaint.exe" for the executable file. To make the file association permanent for GIFs and JPEGs, check the box labeled "Always use the selected program to open this kind of file."
Click the "Image" menu option after Paint opens and loads the image. Select "Stretch/Skew" from the menu.
Enter a new size for the image. The width and height displayed is a percentage. Therefore, you must enter the new size. For instance, if you want to make the image slightly larger, enter "125" and "125" into the width and height text boxes. This enlarges the image size to 125 percent of the original. Click the "OK" button to change the image size.
Click the "File" menu option. Select "Save As" to save the image to a new file name. Click the "Save" option to save it to the current file name.
Enlarging images with Microsoft Paint can cause distortion in the clarity of the image. Newer and more advanced applications like CorelDRAW and Adobe Photoshop enlarge images with less distortion.