ok make absolutely sure u have set the jumpers the correct way round and that the hdd is master, same with the optical drive be absolutely sure the the jumper is set to slave. now on the ide ribbon make sure the hdd is on the end of it with the optical drive in the middle, the longer end of the ribbon is should be coming off the mainboard.
one more thing, make sure both drives are piggy-backing off the psu plug

u will know the optical drive is physically working if the open/close mechanism works.