10. Falling Into You, Celine Dion - 32 million copies 
9. Sgt. Pepper’s Lonely Hearts Club Band, the Beatles - 32 million
copies 
8. Come on Over, Shania Twain - 36 million copies 
7. Bat Out of Hell, Meat Loaf - 37 million copies 
6. Dark Side of the Moon, Pink Floyd - 40 million copies 
5. Saturday Night Fever, the Bee Gees/Various Artists - 40 million copies 
4. Their Greatest Hits, the Eagles 
3. The Bodyguard soundtrack, Whitney Houston/Various artists - 42
million 
2. Back in Black, AC/DC - 42 million copies
And the Winner Is...
1. Thriller, Michael Jackson - 108 million copies
I think that this ranking is permanent, because nowadays, just a few people buy original albums. The World has discovered the internet, so we can download almost everything using torrent, P2P, P2M, Usenet, direct links. Anyways, thats the future. Some band, like Coldplay and Nine Inch Nails are offering online services (free songs download, donations) and thats how they're going to make profit.
Nine Inch Nails put a new album on there website for free, so you could download, listen and donate if you want. They got more than 20 dollars for each downloaded album. \o/
