First SACD to Listen To?

I suggest Jorma Kaukonen's "Blue Country Heart," with stellar back-up including Sam Bush and Jerry Douglas, and even Bela Fleck on a couple of tracks.
I'm sure you will receive many other worthy suggestions. If you know Jorma and Hot Tuna, you will like this album a lot.
It is a very well recorded SACD and the music is terrific.
Whatever you choose, it would be best to stick to an SACD that was recorded using DSD instead of an older recording that has been remastered, even with DSD.

Whatever you pick wouldnt it make sense to listen to something you actually are familiar with? Anyone can love a pristine recording but to understand what SACD truely can do you have to know what you are hearing. Dark Side Of The Moon get your blood flowing?...that sounds great SACD.

Ncarv - I bought that recording on CD a few years back. I didn't know it was available on SACD. It is a great recording, even on CD. As to the first disc? I recommend Chesky's World's Greatest Audiophile Vocal Recordings. Very simple, pristine sound with a lot of space and air. Definitely "audio demo" stuff, but I think the music is worthwhile, especially Kenny Rankin singing Round Midnight.

Beck's "Sea Change" is the one sacd that I would recommend. What kind of music do you like?

Two great options with either Beck's "Sea Change" or The "Blue Country Heart" by Jorma. If you don't have the cd versions of these, get them as they are both great albums. If you have them already then you can do a direct comparison which will be useful.
The problem you have as I see it is the Oppo. I have the same player and am not impressed with it's audio performance. I recently moved it into the living room where it does video duties only.