This is gonna be different:
1. High Anxiety - I'm a huge fan of comedy films, especially those by Mel Brooks. His tribute to Alfred Hitchcock's movies in this is superb, with the twist into comedy. It mixed all of the classic Hitchcock firms into a good storyline that has it's moments of genius. Mel Brooks singing the song High Anxiety is certainly also something to watch. It just seems great to me and underrated.
2. The Naked Gun - God, do I love this series of films. Leslie Nielsen was an absolute treasure, and he is already being missed. His straight talking in this just made the comedy even sweeter, and I keep meaning to rewatch the films as part of my own tribute to him. I will do this tomorrow for sure!
3. Hot Fuzz - Oddly, one of those films that I really like, even though I find the idea perhaps not to my taste. I'm not a huge fan of gore and violence (some of the deaths in this made me squirm in my seat), but this film is one of those films that oozes British but not in a stereotypical way (unless every village is really like that one in the film. Nearly spoilt it there!) Simon Pegg and Nick Frost also are the perfect comedy duo, once again proved in film.
4. Pirates of the Caribbean - At Worlds End - Perhaps my favourite of the series so far. I don't know why, logically I should prefer the 2nd, due to it's wow factor, but this neatly rounded the series off, and did provide a good film, despite being a conclusion to a sequel, which is a rarity nowadays. The scene where the English captain is just walking calmly down his ship as his world (and vessel) falls apart around him just gets me every time. The film never really falls flat either, which definitely puts it on my list.
5. Zombieland - It's interesting, I said earlier I hated gore, yet horror seems perfectly fine in my world. I'm one huge contradiction. But, the reason why this is on my list is the interesting way the story goes. It doesn't begin really at perhaps where you'd think, with the first infections, but in the middle with the character meeting Tallahasee (spelling?), and then going back in the past for the backstories, which is clever. I also love how the "rules" of the apocalypse appear in the film, like a comic book. It's quite ingenious.
As the thread asks for top 5, that's mine. Yet, I feel others need a mention here now, with a short reason why they deserve that said mention -
Psycho - definitely a classic from Hitchcock, and did create the start of humans being the monsters in horror films and the like.
Star Wars Episode V - Seen as one of the best in the series, and I can see why. One of the most known endings ever, that definitely wasn't expected at the time, amongst other things, such as the epic Yoda, the incredible battle at Hoth, as well as the scenery just seems alien.
Super Mario Brothers - Boy, did this get some negative criticism from fans of the franchise (including one Nostalgia Critic). I personally didn't mind the movie. I mean, it was an OK movie, but as it had Marios name in it, people expected some more relevance to the franchise instead of this. It just has some nostalgia feeling when I watch it, both good and bad.