You "have the rack alredy"? What the hell does that mean?
Saying everything is ready is not helpful. Checklist: do you have a PC; do you have the Sonic Riders disk; does your PC meet minimum requirements; have you tried inserting the disk and following the autoplayed instructions (if there's no autoplay go into My Computer, right click the drive (probably D:) and select Autorun I think it is)?
Judging by the post, however, I'd suggest getting a responsible adult to do it for you.
