I loved The Grifters with Angelica Huston, Annette Bening & John Cusack, & Leaving Las Vegas (both dark).
I loved Lone Star, as a movie, AND i have to admit that although most male movie stars leave me cold, Chris Cooper in this melted my cold,cold, heart.
I'll second Crying Game,As Good as it Gets, & the Commitments.

And, I really,really, enjoyed American Beauty -- what a great acting job by Chris Cooper, so obviously unlike what i hope is his real personality, as portrayed in Lone Star :)