Might have been that crummy-sounding MCA release of E.T.. From 1992 through '95, I was mainly buying stuff on cassette tapes. It wasn't until 1996 that I started buying primarily on CD.
Maurice Jarre's Tai Pan. I'd had the LP and knew the recording was impressive. So I bought this so I could use it to test out hi-fi quality when I was buying one. Imagine the faces in Beaver radio!
Dances with Wolves on Epic. Bought my first (and only - still going strong) CD player from Richer Sounds then went to the Pallisades HMV and bought the CD.
In 1985 was traveling from Malaysia back to the states with a stop in Hong Kong. I bought a Sony D-5 CD player there because I knew that was the future In a Hong Kong record shop I bought the Star Wars 2-cd set and Raider of the Lost Ark single CD.
The next stop Hawaii where I saw Cocoon. I got Cocoon there in part because it was the first soundtrack listed in the end credits as being avail on LP, tape, and CD.
I still have all three of those albums on my shelf, but they have been superceded by expanded versions, sometimes twice over.
Young HORNER orchestral soundtracks were perfect for the new CD medium in the 80s.
In December 1987 I bought AN AMERICAN TAIL, my very first CD ever, any music genre. Few months later I took GORKY PARK and eventually WILLOW (in Amsterdam Boudisque record shop, I wonder if it still exists).
It wasn't until 1996 that I started buying primarily on CD. 
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