If I had to recommend one album to intro someone to Sean P, I'd say "Money Barz" (the album I mentioned above). Straight-forward NY street raps about punching people in the face over gorgeous soul sample beats. His other two albums, "Jesus Price Supastar" and "Mic Tyson", are both of similar quality and also worth checking out. King Kong is a nice highlight off Jesus Price Supastar. He's also got a few mixtapes as well as the Heltah Skeltah albums ("Nocturnal" is a damn classic).
Sean Price is a legend and one of my favourite rappers. His music is without a doubt worth giving a shot.