Is fiberoptic or HDMI is better?

To answer your first question, HDMI can do everything optical can do and more. Optical is limited to 5.1 surround sound formats and it can only p two channels of uncompressed PCM. HDMI not only handles up to 1080p video, it also can handle up to 7.1 compressed or uncompressed surround sound. If you have an issue with electronic disturbances get the shortest HDMI cable possible with shielding.