Its very easy process dear have a look at following points:-
1. Start on the right foot. Open a blank document in MS Publisher. Prepare to insert your image by clicking INSERT on the menu, then PICTURE, and likely FROM FILE.
2 Get the picture. Locate the image you want to use and insert it onto the blank page in Publisher.
3. You can determine the current resolution by clicking SAVE AS. The resolution for this image is 190.
4. Make a shape. Create a circle or square, and double click the shape to format it. Change (format) the shape to have NO FILL and NO LINE.
5. Group your objects. Place the shape, which is completely transparent, on top of your image. Using your mouse, click and drag to form a "select box" around both objects, or CTRL-click on the two objects to select both together. Right click and select GROUP. Click on the small box with the dots to attach the objects together.
6. Up the resolution! Right click again and select SAVE AS. Just above the file name you will see the default resolution, which is usually 150dpi for desktop printing. Select CHANGE and select the 300dpi option.
7. Save with your desired file name and you are done!