Halo 3 solo player wont play?

[shazee]

ok so i had started my campaign on halo 3 a while ago but i never finished it i have recently decided to play again but everytime i hit resume solo it will show a scene from where i last left off and then go to the main menu

 

[Enjoi]

the disc is scratched.. but then again if the level wouldnt load it wouldnt show 100% in the percent bar and wouldnt even let you accept it so idk...