4. The Simpsons
Why You Should Watch It: Unless you were literally born, like, right this second, you know what The Simpsons is. It's the longest running, most recognizable and, at one time, the most hilarious animated show ever made. If that's not enough to sell it, then your standards are probably unjustifiably high and you can't be helped.
Why You Should Watch It Again: In its prime (more or less between season 3 and season 13 or so) The Simpsons was by far the funniest television show on air. The wit was a perfect blend of silliness and cleverness with just the right dash of pop culture. It is easily the most quotable show ever, is it not? Those lines you have stuck in your head are as much a joy to watch be delivered now as they were the first time you experienced them. The Simpsons is a rare thing, in that it is a show that seems to be funnier because you know what's coming next. You've seen it all before and it is so unforgettable that, upon rewatching it for the zillionth time, you find yourself lip syncing Homer's exact line right as he says it. And there is some sort of unexplainable satisfaction in doing that. And even more satisfaction in the fact that it's still funny. Something not a lot of people realize is just how many pop culture references there are in show. Probably every single movie you've ever seen has been referenced, spoofed or mentioned in The Simpsons. And that's not even including the Halloween specials. It's a very enjoyable thing watching an episode down the line that you've seen numerous times already, but finally understanding a joke because you've seen the particular movie it's in reference to. And you'd better believe that this will happen lots of times.