You need to use your keyboard; it's a DOS environment so mouse isn't really supported. Just use the Tab and/or arrow keys to get to different sections/buttons and the Enter key to select.
When you're in the program, you can use the Alt keys to open the drop down menus, and the arrow keys to navigate said dropdown menus.
When you're in the program, you can use the Alt keys to open the drop down menus, and the arrow keys to navigate said dropdown menus.