10 discs to complete my collection? I don't think any number of discs will ever complete my collection. Just when I think I've obtained the last missing piece, something else gets announced that I just have to have!
16 posts and nobody's mentioned Song of the South? I'm impressed! (for the record, it's not in my top 10)
Mine would include:
The early movies of Paul Verhoeven (i.e. Soldier of Orange, The Fourth Man), which seem to have gone out of print.
John Waters' Mondo Trasho (will likely never happen...