Below is a 4.8GB wii download from newzbin, the extra are recovery (par2) files, all current Wii burn to single layer.
105 files, 91 data, 14 recovery
Encoded: 4,393.8MB data + 451.1MB recovery = 4,844.9MB total
Decoded: 4,218.0MB data + 433.1MB recovery = 4,651.1MB total (estimated)