For various reasons, names that I think will be remembered years from now:
Tom Hanks (No. 1 imho)
Steven Spielberg
Harrison Ford
Clint Eastwood
Julia Roberts
Jackie Chan
James Cameron
Michael Jackson (pioneering cinematic music video, among other obvious reasons)
Sylvester Stallone
Bill Murray
Stan Winston (obvious contributions to the industry)
Meryl Streep
Arnold Schwarzenegger
Brad Pitt
Robert De Niro
Sean Penn
I'm sure there's many others, but these are the first majors that come to mind...