Kate Winslet..because she is a talented goddess
Salma Hayek...mostly just the eye candy
Gretchen Mol...she's cute and talented, and doesn't work that much
Emma Thompson...she has more talent than most people, in any genre
Dakota Fanning...she is that good
Miranda Otto... i saw some of her indy films throughout the last year, good stuff, especially Julie Walking Home.
Emily Mortimer....foreign affair, young adam, and lovely and amazing are recent favorite flicks...
Joan Cusack..she's always good...always.
Natalie Portman...she is talented, she just needs proper directing and asolid script.Leon and Garden State prove this.
Then I'd say Naomi Watts or Charlize Theron..both are capable, but haven't gotten the greatest roles IMO, they have talent though..

Johnny Depp...best actor working period
Ewan McGregor...2nd best actor working, see Young Adam, Moulin Rouge, etc...
Morgan Freeman...always makes a movie better
Jude Law...the new Cary Grant
Paul Giamatti...great supporting actor that could play a lead
William H Macy..he can do anything, very powerful..he seems more "real" than any actor
John Cusack...guilty pleasure, I enjoy all of his films..reminds me more of Jimmy Stewart than Tom Hanks...
Brendan Fraser..highly underrated...Still Breathing, the quiet american and Gods and Monsters are 3 of my favorite movies from the past 20 years, all 3 are excellent
Robert Redford...well, he's starred in a boatload of my most memorable movies..the Natural still makes me cry and the Horse Whispere tugs at my heart strings and that damn jeremiah johnson is one of the finest films ever.
Will farrell..hilarious...
Jean Reno..his films are always great from leon,ronin to wasabi...