5. Fear of the Dark
When this album came out, I hated it. It was a drastic change in the sound of Iron Maiden. The change started with the prior album, No Prayer For the Dying, but that still had some traces of their earlier vibe, this was quite different. However it has become one of the albums I put into the CD player most. Many of the songs are more radio friendly, less about fantasy and more about love and life, which isn't the kind of stuff they normally wrote about. In hindsight though this album is very well written and has a number of songs that work very well like Wasting Love, Be Quick or Be Dead, Fear of the Dark, Fear is the Key, Childhood's End and Judas My Guide.
I really wanted number 4 to be Number of the Beast (and I am sure a lot of people would put it at number 1) but I have to choose Powerslave for a few reasons. One is personal. My cousin and I both learned to play guitar at the same time and he figured out a bunch of songs from Powerslave a day after he got his first guitar, so they are really burned in my memory as a result. The other reason is it has some of their greatest songs ever. Two Minutes to Midnight and Aces High are the two most memorable Iron Songs. The song Powerslave is excellent and Rime of the Ancient Mariner is a wonderful 13 minute epic.
3. A Matter of Life and Death
This is one of their more recent albums (2006) and while I grew up mainly listening to their older stuff, I have to say the newer material is really good and it feels they've aged well as musicians. I probably wouldn't have been as fond of this album when I was younger, but I quite like the sound they achieve. There newer stuff is a bit more epic and melodic. I particularly like The Reincarnation of Benjamin Breeg, The Pilgrim, Lord of Light and The Legacy. If you are an older fan who has been hesitant to hear their newer material, I strongly suggest starting here (Brave New World is great as is The Final Frontier).
2. Piece of Mind
I thought this would be my number one, but I don't think I have listened to it quite as much as the next album. This one has some of their greatest songs in my opinion: The Trooper, To Tame a Land, Revelations, and Still Life. Everybody loves the Trooper and Revelations is one of my personal favorites. To Tame a Land is an amazing song about the Dune series (Steve Harris writes lot of songs about books he reads).
1. Seventh Son of a Seventh Son
I love this album and think it deserves to be put at number one. It is from their later period of development in the 80s, when they arguably started sounding more Euro or progressive (beginning with Somewhere in Time) but I feel this sound really suits them and Seventh Son of a Seventh Son has a cohesive feel that is book-ended with a great guitar guitar and vocal section. The music sounds exactly the like the cover looks. It is a bit short, and it doesn't have quite as many individually great songs as some other albums I think, but overall its overall effect is strong. Still there are great songs including: The Prophecy, Seventh Son of a Seventh Son, Infinite Dreams, Moonchild and Only the Good Die Young.