[Open from File] radio button
When you want to specify the file name of the image to be put in the HTML file, this button should be turned on. You may select the image file from "Open" dialog by inputting the file name in the text field or clicking the [Browse...] button.
[Show Border] check box
When you specify a link for an image, a frame is displayed around it. When you do not want to display the frame, this check box should be turned off.