While I know and love a ton of music from 1986 and 1987, 1988 is a challenging year. Even finding 10 albums I "know" and enjoy is a challenge. I only own three on vinyl, and none on CD or cassette.
In 1988, the year I turned 12, I didn't really listen to music, except what my parents listened to and random top-40 radio in carpools to school and practices. And what my parents listened to was: Sandi Patti, Bill Gaither, Michael Card, GLAD, etc. Even my favorite album of 1988 I didn't listen to at the time. I was vaguely familiar with Amy Grant, but I definitely did not hear Lead Me On in full until probably the early 90's. The only other artist listed below that I definitely heard in 1988 was R.E.M.'s singles on the radio. The top 5 below I had all heard and knew by the end of the 90's, but then numbers 6-10 I didn't even discover until after Y2K.