The motor you describe is a STEP MOTOR

A CD ROM drive has three motors, one is uesd to spin the disk and the second one positions the head. The third is there to eject the tray.

The only stepper motor is head positioning. Other two are simple DC motors.

I don't know which motor you have taken out, but if it is spinning motor, then sure it is not stepper. A stepper can't move at such high speed which todays CD ROM drives have.

Didn't you ever hear the sound of a spinning disk?