3 pieces of advice

Film can be whatever you want it to be. That's the beauty of cinema, it's an art form and there for expressive, so you make it whatever you want to express... might be pirates chasing ghosts, a man stalked by the ghost of his dead wife on a spaceship, a body hoping alien stuck in the Antarctic with a bunch of grumpy men, or the devastation of war on an innocent boy, a group of men driving nitro-glycerin at 5 mph across a rocky mountain range... it's whatever you want it to be, whatever story you want to tell, and whatever points you want to make... and if you want to make Wedding Crashers II thats OK too.

Ps. Films broken down were Pirates of the Caribbean, Solaris, The Thing, Come and See, Wages of fear... all must sees.

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I'd try to be a bit more methodical than trial and error. It really depends on what kind of movies you want to make, chances are, whatever they are, they will find an audience and thus be entertaining to that audience. 

What you need to do is learn you craft, if you want to be a writer, learn how to write, buy the books, the magazine, talk to other writers, swat up on it, the same if you want to direct... pretty much the same for every part of it, learn it, know it, be the best you can be at it. You'll find out along the way what works and what doesn't, largely by studying what other people are doing and what audiences are going to.

That might be a bit vague. But I will say this, make what you would want to see and make it from a truthful place, by that I mean, believe in what you're doing, no matter what it is, find the honesty in it. If you do that, the audience will too and you will find an audience.

Here's a link to a good site, check out the colums section and read all of them. They'll give you a good insight into putting successful films together.

Also, check out this place, lots of interviews with writers about their work, you'll get a good understanding of the thought process behind this stuff.

That'll get you started. Enjoy. Hope that helps.

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No. There is a craft to filmmaking, same as there is to carpentry, there's a way of doing things, a methodology. But where as some carpenters bang up crocked timber frames on building sites, others carve exquisite pieces of handcraft furniture while others make funky modern designs. You take the rules and you bend them to make them do what you want to do. 

But if you don't first learn how to make a basic chair and understand the physics of how it works it's just gonna fall apart when you sit in it. Same with film, if you don't understand what makes them work your audience is just gonna pick out all the holes in it. 

You know yourself when a film doesn't work, you can see the plot holes, you get bored, you know when somethings not working and you feel cheated. It's because the filmmakers took a short cut, they left off on of the legs and hoped no one would notice. (OK, enough carpenter analogies! I promise)

Remember, every story has been told, there are only a few basic plots, the trick is to tell it like it's never been told before, with something unique, and that uniqueness is you and your slant on things.