It's a true story. 'Remember the Titans' is inspired by the actual integration of a high school football team and the struggles and achievements that came with it. The characters and events have roots in reality.
Sure, Remember the Titans is true. It accurately portrays the struggles and successes of the players and coaches as they worked to overcome racial barriers and come together as a team.
The Titans comic adaptation has its ups and downs in terms of accuracy. Some characters and plotlines are closely followed, while others have been tweaked to fit the visual or narrative demands of the adaptation. It's a mixed bag.
It's somewhat accurate, but there are definitely some differences. Some characters' storylines have been changed and some plot points are unique to the show.