Michael Jackson's Dangerous gave me an outlook full stop. Before that I wasnt all that interested in music at all. Oasis started to steer me in the direction of more guitar driven music with both (Whats The Story) Morning and Definitely Maybe when I was about 11 or 12 years old.
I then have two main albums that completely started to stir my taste in music up and are probably responsible for 90% of what I listen to today and they are as follows:
Without this I probably wouldnt have developed a love of heavy metal. I wouldnt have discovered the "real" Metallica albums and then opened my ears to many sub genres and more "extreme" forms of metal that makes up a lot of what I listen to now.
I think I can probably trace my desire to wanting to learn about as many different kinds of music as possible back to the purchase of this album. Without it I think my music taste would a hell of a lot narrower.