We just visited your website and see that there are 4 products per row on your shop page. Have you already managed this option in Theme Settings -> Shop?
Images size you can specify in WooCommerce -> Settings -> Products -> Display.
Thank you so much for your quick Response But Can you see the screen shot. I want to upload different size image but show in a default size. How can i do that. Another question is that how can i show Zoom on Hover?