2) That perfect person: in most romance novels, if not most fiction, there is one and only one perfect mate for the protagonist. Their journey to find each other may be circuitous, frought with danger and detours, but ultimately becomes inextricably joined. Even the world itself seems to conspire to bring the two together. IRL, people are not jigsaw pieces to be fit together like a puzzle. They are imperfectly formed, change with time, and often disappoint each other's expectations. Take heed, though. There are seven billion people in the world, and it's not really that hard to find at least one among them who fits well enough.
3) Sidekicks: in a lot of the best stories, there are sidekicks for the protagonist; foils for his bravery, supporters for her self-doubt, surprising fonts of wisdom in times of great need. IRL, we have friends, real people with dignity, troubles of their own, and at least as many faults as we have. We should treat them as such.
4) Good people are always good: like the villian, the hero is ubiquitous in fiction, either a lawful good paladin or a scruffy anti-hero, but always wanting to do the right thing. IRL, heroes are usually just the ones who are in the wrong place at the wrong time, have the presence of mind to see a way out of it, and are slightly less terrified than the rest. The rest of the time, they are pretty much like everyone else, and they are often the first ones to say this.
5) Evil people enjoy the suffering of others: by definition, this seems to be trivially true, and it's one of the most common tropes in fiction. IRL, people who are clinically sociopathic or psychopathic and enjoy the suffering of others often don't really understand that the sufferers are people. This is not the same as a movie villian. As far as I can tell, most evil people are selfish and callous, but don't really enjoy suffering. They don't seem to enjoy much of anything, which is part of their problem. In fact, many people who have been called evil in history lived their entire lives believing that they were doing good.
6) Being bad is fun: since the teenager culture ballooned after WWII, it has become fashionable to believe that a little rebellion when young is a mostly harmless rite of passage. IRL, your parents are usually right when they tell you that getting into trouble is more trouble than it's worth. In truth, most trouble is found by stupidity and accident rather than active trouble-making, but looking for trouble too often leads one to finding more than he can handle. And the morning after is usually only the beginning of a painful recovery.
7) The Evil Plan: it's a much over-played cliché in thrillers; the bad guy has the hero cornered or tied up and smugly tells him exactly how everything has been planned to lead to the world's destruction, usually giving the hero just enough time to get free and win. IRL, bad guys just shoot, they don't explain. Someone in the deep throes of psychosis might, but his explanation is likely to make sense only to him. In any case, a criminal mastermind would not be destroying the world merely for the sake of beating his enemy, he begins by killing his enemies. Destroying the world is much easier that way.
8) Monsters: in fiction, animals are usually the scary ones and people are usually justified in killing them. This is the age-old man vs. nature trope, a metaphor born in a time when we still believed that nature was stronger than us and inextinguishable. IRL, animals are usually tagged, watched closely, or penned, and people can be much scarier monsters.
9) Technology will save you: in movies, the answer to most bad situations is a better gadget. IRL, the answer to most bad situations is trying to relax and think calmly.
10) Technology will kill you: in movies, the biggest danger comes from the biggest bomb. IRL, the biggest danger comes from blind faith.
11) Countdowns: there are countdowns for just about everything in fictional media. Bombs, poisons, how long bank robbers will give before they start killing hostages, etc. IRL, about the only countdowns you'll see are rocket firings, and these are mostly to make sure all the buttons are being pushed at the right times. Bombs generally have either time-delayed fuses or dead-man switches, but rarely clock faces that count down. Basically, if you see a countdown in a film or TV show, it's for dramatic effect; in the real world, bad things don't wait to happen. The effects of most poisons are cumulative, acutely symptomatic, and very rarely fully reversible. As far as I know, there are no poisons that can kill within a set time frame, much less be completely undone at the last minute. If you're ten minutes into a twenty minute poison, you're pretty much dead whatever you do. In any case, there is irreversible damage. Although there may be people who follow the rules of popular movies when taking hostages, they are by far the minority. Most hostage-takers are irrational, nervous, and apt to follow no rules. If they are going to kill their hostages, it's more often than not for personal reasons, and they don't use a clock to toy with the police.
12) Related to above, Fail-safes: every bomb shown in film seems to be rigged to blow if it's tampered with. IRL, this is usually an added complication that no one bothers with. Bad guys might use them, but more likely will try to make their bombs go off before anyone knows they're there. Armed forces, on the other hand, do the complete opposite. If they have fail-safes on their weaponry, it's to shut them down if tampered with. The bigger the bomb, the more likely they will make sure that it will only go off when they want it to.
13) Self-destructs: again, in film and books, every big weapon, vehicle, or energy using device seems to come with a self-destruct mechanism. IRL, these only exist as booby traps in the most paranoid of nutjobs' homes. Militaries will have plans to scuttle ships or crash planes if they are taken by the enemy, but never by self-destruct. That is basically admitting that you expect your ten billion dollar ship to be taken by pirates, and no one will admit that, much less endanger every crewmember just to keep the bad guys from winning.
14) Magical words: in fantasy stories, words have power backed up by the will of the speaker, and use of the right phrase can do just about anything. IRL, words have a different kind of power backed up by the wills of the listeners, and use of the right phrase can do just about anything.
15) Magical things: once again, in fantasies, people can instill power into various items to make them special; swords, gems, and books are common. IRL, things are what they are, and are only as special as what people use them for. Swords cut, but cannot make a boy into a king. Gems sparkle, but cannot make a girl into a queen. Books can hold great wisdom, but they cannot make someone wise.
16) It's good to be the king: as the aim of most fictional villians and the birthright of forgotten princes and princesses, being the supreme leader brings with it the acclaim of the masses, the fear of enemies, and uncountable wealth. IRL, leadership is a neverending struggle against doubt of self and everyone close, a fathomless labyrinth of politics and beaurocracy and, for the ambitious, all too often the opposite of what they fought for. It is not from envy that the throne has been called a golden cage.
17) Happily ever after: in one-off fiction, this is still the preferred way to end a story, with most plotlines neatly tied and all of the major problems resolved. IRL, every day is different, with its own little triumphs and tragedies and possibilities of great victories or horrific ends. There is only one ever after, whether it comes happily, sadly, or just comes; until then, it's play it as you go. And the plot goes on whether you're in it or not.
18) Fate: like its warm, fluffy ultimate end in fiction, living happily ever after, fate is used as an anchor for readers. It gives the protagonist a purpose in life, sets him on a journey with a foreseeable end, and guides him along that journey with signs and momentous events. IRL, we are all born naked and helpless, with no future foretold for us but the airy dreams of our parents. Life is far more complicated than we can possibly imagine, and the world at large cares not a whit whether we win or lose, get what we want or end up dying in a gutter. We must be the captains of our own fate, write our own story, and create our own purposes.