The first I remember receiving was the Dobbie Brother's Greatest Hits as a Christmas gift.
Like others here, I bought Grease early on; might have been the first I bought.
I also had the Star Wars soundtrack as well as a Star Wars record with much of the movie audio on it.
Then a recall my short lived KISS phase including the solo Paul Stanley LP.
I also remember getting the single for Meatloaf's End of Time (if that is the title) but no really processing it was about sex.