1. Load ImgBurn.
2. Switch to 'Read' mode...
2a. You can do that via the 'Create image file from disc' button on the 'Ez-Mode Picker' screen.
2b. Click the 'Mode' menu at the top and then the 'Read' option.
3. Insert the source disc in the drive.
4. Click the 'Browse for a file' button and select a name and location for the destination image file. (Or just accept the one generated by the program)
5. Click the big 'Read' button.
6. Wait a while zzzzz.....