Lord of the Rings, Gladiator, The Usual Suspects, Old Star Wars Trilogy, Braveheart, Indiana Jones and the Last Crusade, etc.
(Honestly, though, it's really hard to name the top ones, especially those I've not seen in a while... I mean, there are a lot of very good movies that I simply forget about in lists like this that may not be very top like Star Wars and the like, but are truly deserving of merit. Say, Princess Bride which someone just mentioned. Very good movie right there.)