Hmmm......tough one. Ok, i'll give it a go. In no particular order....
Ozzy Osbourne - Diary of a madman. Quite simply a masterpiece. Worth buying for the title track alone which blends an orchestra and choir with Randy Rhodes razor sharp guitar playing, rock, metal and classical collide with stunning results. Ozzy's first two album's were classics, forget the rest.
Queensryche - Operation Mindcrime. Gotta agree with Serval on this one. Concept albums dont usually work but this one is awesome. A tale of an Orwellian 1984 style underground world where big brother does more than watch. The track "Revolution calling" steals the show and is amazingly catchy. I was lucky enough to see them play in London on the 'Mindcrime' tour where they played the whole album live, including the eriee atmospheric's between the songs "...perhaps you need another shot?"
L.A. Guns - Hollywood Vampires. Brilliant mix of driving rock music from the haunting ballard 'Chrystal Eyes' to the slow burning sheer brilliance of 'Over the edge'. Seriously under rated album, one of rocks best kept secrets.
Aerosmith - Get a grip. Could easily be a greatist hits album as it has so many hits on it. The centrepiece is the classic 'Living on the edge', a moody self destructive hard edged song which could easily be the soundtrack for the end of the world! There is also Crazy, Cryin, Amazing (all massive hits) along with Eat the rich, Fever and Flesh which Tyler uses as vocal punchbags....awesome!
Scorpions - Lovedrive. I was going to put Blackout instead but Lovedrive has Holiday on it so that won. Yep, this band proved that Germany can produce brilliant bands. The aforementioned Holiday is an acoustic guitar track with Klaus Miene singing over it, and then has an all out heavy bit in the middle (similar to Led Zep's Stairway..) There is also the bizarrely named 'Loving you Sunday morning' and the even more bizarre 'Another piece of meat' ("Hey lets go, dont put on a show, you're just another piece, another piece of meat") Class! Why do I keep humming Blackout though?
I do have Elvis Costello, Billy Joel but the next song might be something from Iron maiden or Rammstein. 
(Also Smile) 
