Proably my favorite album of all time is Metallica's Master of Puppets. Got to play "Orion" at my high school talent show, and I was popular for 15 minutes.
Speaking of high school, this came out just after I graduated in 1997. Being a metal fan in th 1990 's sucked, but then this cme out. It's the first album I bought as a new release that I feel stands with classics from years before, Bruce Dickinson's Accident of Birth. Starts out heavy, but then the mood kicks in tracks 4 - 8 and after a few more metal tunes, closes with a couple of beautiful softer tunes. This is how you sequence an album.