I meant to physically switch them such that the disk drive is at the end. I wouldn't try and make the DVD the master.

Each IDE device has it's own termination (sort of) for the same reasons that SCSI busses have it. The SCSI system of end termination is more reliable, but requires a bit more thinking to set up.

Oh, yeah, if it is ringing causing your problems, you can slow down the ide interface clock and it should work.