Depends on the quality of the DAC's in both the CD player and Reciever. If the reciever has a better DAC, then using an optical will yield better results. If the CD player has a better DAC, then the analog cables may actually be better. So, without having any more information on what models you are hooking up, the answer to your question is there could be no difference or there could be a lot of difference.
The Receiver is a Yamaha V495 (2 or 3 years old), to be upgraded to an Outlaw 1050 within a year. The player will be something like the Sony CDP-CE375. I have used my DVD player to play CDs up until this point, but I'd like to have the ability to play burned CDs.
Another thing to mention is that many receivers don't have analog bypass. What this means is that the analog connections from your CD player could be redigitized & processed by the receiver (lowering sound quality). Analog bypass passes the full analog stream directly to the amplification stage. I don't believe the Yamaha has this feature, so the digital connection is probably optimal.
Ahh, Dave, I feel your pain. I was without my CDP for about a week and had to use my DVD player as a CD transport. Being an older DVD player, it doesn't play burned discs. Ouch! Didn't realize how much I listen to my own mixes until I couldn't play them (I wonder how much my desire to play my burns was fanned by my inability to do so ).
If you're considering picking up a CDP so that you'll have the capability of playing burned discs, I'd agree with Greg and recommend a digital input given your receiver. If you're out of digital inputs, however, I wouldn't let that hold you back from NOT getting a CDP. The analog input, at least in my estimation, probably won't be BAD and the ability to play your own mixes might far outweigh any negatives.
Just my humble opinion. YMMV.