Click the Chevron to the right of the Burner field. A drop-down menu will list the choices.
If your burner isn't one of them, then the PC apparently isn't recognizing it. Can you play DVDs with that drive? Try a reboot.
An image file can be created, and later burned to DVD - using the appropriate software.
In recent Windows versions a right-click on the ISO (image file) should offer a Burn Disk Image choice.