A question like this is hard to get a good anwer. Because of the different genres and sub-genres of music that all have outstanding artists it would be impossible to say what is the "best album" for a particular year. Not to mention that everybody has a different taste in music.
For me
Rock: Along Came a Spider - Alice Cooper
Metal: All Hope is Gone - Slipknot
Death Metal: Till Death Do Us Part - Deicide
