I went to a local flea market about two months ago and there was this family selling their PS1 (this is the original model, not the PSOne model) system with games. Most of them were PS1 sports titles and some kids titles. The one title that stood out was DDR Disney Mix. It was complete, but the disc was in horrible condition (covered in sticky fingerprints, scratches all over the back of the disc). She said that she wasn't selling the games separately, only as a package with the system for $150! YEAH RIGHT...
I ramble on... congrats on the nice find.