@Tillman:
1. You are using Catch Box Pro theme, which is build in responsive design. So, when you use the table you need to use responsive table. Better I suggest you to use Responsive Column. You can use install responsive column plugin and add the image on it. Then you will not have image issue.
2. You table is larger in 100%. As you have used 4 td elements each 25%, but you forgot the padding that each td is taking 10px each at the right and further it has border on it.
3. Ok you can remove the border and padding in your image by adding in the following css in “Appearance => Theme Options => Custom CSS” box.
img[class*="align"], img[class*="wp-image-"], #content .gallery .gallery-icon img, img.wp-post-image, img.attachment-thumbnail {
border: none;
padding: 0;
}