I'm not a big John Wayne fan, but I do generally like his films. When Wayne was on, he was dead on. When he missed, he missed in a big way. Wayne was basically a one trick pony, but that was a good one. No one played western's better than he. But he also had some terrific bombs in his carreer too, mainly when he tried to step outside of that role.
My favorite 3:
The Cowboys
The Searchers
True Grit
My least favorite:
Jet Pilot
McQ
The Green Berets
Jet Pilot had all the wannabe action of Top Gun combined with the intelligence of Iron Eagle II. It had some excellent footage of F-86's in action...