It seems that the best way to ensure record-breaking sales of a videogame is to have it included as part of a console package. Tetris was bundled with Game Boy purchases and reached 35 million sales. Super Mario Bros was bundled with the NES and surpassed 40 million sales. But, thanks to the popularity of the Wii console, Wii Sports takes the crown with over 76 million sales.
If you expand the parameters to include both paid and free mobile phone downloads, it’s noteworthy that the various versions of Tetris on mobile phone platforms have exceeded 100 million. However, Angry Birds reigns supreme with over 250 million downloads for various platforms.
Wikipedia: List of Best Selling Video Games