Hmmm. I'd kind of forgotten the good music in Titanic (and by good music, it's basically just Gaelic Storm down in steerage and then the chamber music) is on the other soundtrack album, Back To Titanic.
For what it's worth, a friend of mine and I were talking about movie soundtracks earlier today, after I called "The Harder They Come" the greatest soundtrack ever released. A quick check...it peaked at #140 on the Billboard charts.
I wore out my tape of the Blues Brothers soundtrack. Others I have loved: Stand By Me, Animal House, Grace of My Heart, (discussed here more than once), Pretty in Pink. The movie that never put out a soundtrack that should have? Ferris Bueller. My high school boyfriend and his best friend put one together - back then that was a painstaking process. I loved that tape.
A few great 80s soundtracks for me were Valley Girl, Streets of Fire and Some Kind of Wonderful. Loved the Pretty In Pink soundtrack as well. By the way, these occasional Dave Holmes "Somewhere in Time" features - generally they're recaps of Top 40 charts from yesteryear instead - are absolutely amazing.