Hopper IS a great actor. If you doubt me, check out the scene in TRUE ROMANCE where he faces off with Christoper Walken--one of the greatest in movie history (unless you're Sicillian, that is). Hint--Hopper is the normal one.
That is a great scene in True Romance--full of Tarantino dialogue :)
Also want to remind everyone he played the son in the movie GIANT. The sensitive son who wants to be a Dr. and marries the Mexican woman.