The Game Boy Color game is a role-playing game, similar to games like Final Fantasy. The player controls Harry, starting from when Hagrid brings him to Diagon Alley. It strictly follows the story of the books, with all the scenes from that point on in the book being playable, except for the addition of bands of monsters such as rats, bats, and spiders roaming most of the locations. The spells are used for combat, rather than interacting with the environment.
Source: Wikipedia, "Harry Potter and the Philosopher's Stone (video game)", available under the CC-BY-SA License.