I'm sure if I thought longer I would add to the list, and many of my choices are previously mentioned here already, but I generally would post almost any of John Wayne's films to a list. A lot of Bruce Willis's movies were forgettable but when he "hit his stride" with the right script he was hard to beat.
A child of the fifties, I like a lot of the old b&w noir classics, and back when stars were stars and most of their less than admirable behavior was not common knowledge, I always enjoyed most any of the films with Gregory Peck, Robert Mitchem, Jimmy Stewart and Cary Grant.
A lot of the folks here definitely seem to like the ones with gunfire, explosions, and car chases (ah, Steve McQueen . . . ), I mean, who doesn't ?

So my "favorites" list is quite encompassing.
I find it difficult to name an 'all time favorite', but I seem to keep coming back to one in particular, and I've tried to analyze "why?" and find it hard to explain. Tom Cruise's "
A Few Good Men" with Jack Nicholson, Kevin Bacon, Kevin Pollak, Keifer Sutherland and Demi Moore stands out in my mind as just an absolutely fine film. Not really an 'action' film (no gunfire, explosions or car chases

) I find the story/writing compelling and the performances top notch - everyone in the movie down to the minor characters gave great performances. There was tension, chaos, subterfuge, good guys who were bad guys, flawed humans caught in the blurry area between doing the wrong thing for the right reason and coming to the realization too late, and a conclusion that satisfied justice, the victory of morality over an imperfect system, and the triumph of the human spirit with the true villains getting their due, and even some lighthearted humor in the subtext. In this movie I consider it a modern classic, in that
the story was the star - not the actors, not the action, not special effects - a throwback to the great films of the past in a market today where all those things I mentioned are not there because there's very little "story" to the plot that allows good character development to draw out true human emotion and compel the viewer to care about the characters.
Don't get me wrong - my baser self loves watching Clint Eastwood, Bruce Willis, Sylvester Stallone, Jason Stathom, Tom Cruise and all the new crop of actors wreak havoc on all the bad guys for mindless satisfaction and short term diversion from life's duller side. I can blithely sit down and watch most any of most them numerous times. But few of these offerings are like a good book, where the story is so good the characters take a secondary place. I get pulled into "
A Few Good Men" every time I happen to come across it on the tube.