Some stats on JAPAN:
Wii Fit: Duration 20:37, 20.26 sessions
Wii Sports: Duration 30:00, over 28.44 sessions
Zelda 3: Duration 9:44, over 7.51 sessions (21,282 registered sales)
Zelda TP: Duration 50:10, over 21.36 sessions
No More Heroes: Duration 10:44, over 5.12 sessions
Resi 4 Wii: Duration 33:23, over 15.41 sessions
Umbrella Chronicles: Duration 14:54, over 8.61 sessions
Dr. Mario WiiWare: Duration 14:09, over 9.24 sessions (13,931 registered sales)
FF:CC My Life As A King: Duration 21:14, over 8.89 sessions (33,810 registered sales)
Star Soldier R: Not enough data/Data withheld
Everyone's Pokemon Farm: Duration 8:03, over 17.98, but... 44,779 registered sales