It is followed by last week's number one LEGO Batman 2 in second and Skylanders: Spyro's Adventure, which climbs to third.
With the exception of Mario Kart Wii dropping to fourth, the remainder of the chart is unchanged from last week, leaving FIFA 12 and New Super Mario Bros propping up the rear.
The top ten in full:
1. (2) Mario & Sonic at the London 2012 Olympic Games (Sega)
2. (1) LEGO Batman 2: DC Super Heroes (Warner Bros Interactive)
3. (4) Skylanders: Spyro's Adventure (Activision)
4. (3) Mario Kart Wii (Nintendo)
5. (5) Zumba Fitness 2 (505 Games)
6. (6) Mario Party 9 (Nintendo)
7. (7) Zumba Fitness (505 Games)
8. (8) Wii Party (Nintendo)
9. (9) FIFA 12 (Electronic Arts)
10. (10) New Super Mario Bros Wii (Nintendo)
Leisure software charts compiled by Chart Track, (C) 2012 UKIE Ltd.
Watch The Wanted play Mario & Sonic at the London 2012 Olympic Games below: