I cant get the surround sound to work after connecting the Samsung BluRay Player to my Onkyo reciever using a optical digital connection or directly with the HDMI cable ?

Basic DVD player hookup to TV cable diagram. RCA cable (yellow) video and RCA cables (white and red) audio. This is all you need for picture and sound. If your TV only has a single RF input, then you need a RF modulator. RF modulators accept the yellow, white and red cables and output a coaxial cable to the TV single input jack. Usually the TV is tuned to channel 3 or 4 to pickup the RF modulators output.

Alternative connection options are many and include HDMI for HDTVs, component video and for sound, surround sound digital audio connection using optical or coaxial digital audio cable.

Surround sound requires a decoder such as a A/V receiver with Dolby Digital 5.1 or DTS 5.1 or more. 6 speakers connected to the A/V receiver surrounds the listener.

Bluray players will play DVDs and Bluray discs. Bluray gives you High Definition video and typically connects to a HDTV using a HDMI cable.
dvd_howtoconnect.htm
for more information and pictures on DVD player hookups.