Hi ruthstory,
The problem could be with the Power supply/ motherboard. To isolate the problem, please power on the system and try to eject the optical drive and check if that ejects.
Also check if the hard drive status light is lit after switching on the system, this light is present below the power button. If the optical drive does not eject, and if the hard drive status light is not lit then the power supply unit needs to be replaced, else the motherboard needs to be replaced.
To replace the power button, refer the topic ‘Removing the Front I/O Panel’ in this link: http://bit.ly/12gbejO
Please post the results for further help.