The first LP I ever bought was Band on the Run by Wings. Though the title track and Jet were great singles, that rather embarrasses me today.
I suspect the second LP I bought was Simon and Garfunkel's Greatest Hits, which does not embarrass me at all as Paul Simon is one of the great songwriters of the post-war era.
This recording of America is taken from their 1981 concert in Central Park, New York.