Non hdtv receiver

I need your help.I have an old receiver YAMAHA RX-V2095 ,EOSONE RF 1000 main speakers plus center and rear speaker EOSONE also.I have a brand new PANASONIC HDTV television and hdtv panasonic dvd.The Yamaha receiver is lacking for HDMI in and out,I do not have the slightest intention to throw away that YAMAHA,What would it be the best connection for audio and get the most of sound even when is not HDMI.I was thinking of OPTICAL,I need your opinion,thank you

Not,it is just a DVD player,thank you,it has hdmi output,thank you for your help

Thank you,and then what can I do when I ger a new blueray player or PS3?I mean just with this YAMAHA receiver,not buying a modern one with HDTV connection