Nothing shows up because Wii games use a special filesystem that Windows doesn't support. Use the Verify mode to check your disc against the image, and next time leave Verify enabled, it's enabled by default for a reason!
What's your E: drive? USB external or network drive? It's too slow for 12x burning. Also you might get a better burn quality at the slower burn speeds (they're listed in the Supported Write Speeds field of the media information text).
//edit oops too slow again