I'd like to start off by first saying that I have always thought about this and it has been hard to get my list down to a Top 20 let alone a Top 5. Not only do I feel like the five I picked could combine for a force like no other, but each of them has always meant something to me as well.
#5 The Flash (Barry Allen)
The Flash is a character that I have always thought to be overlooked much too often. One thing I have always loved about him is that his powers aren't completely over powering. He can run fast and heal quickly, but it's not like he is invincible. Yet he constantly fights off meta-humans with crazy, deadly powers to save the day. Plus the man can travel through time for crying out loud! How badass is that? The Scarlett Speedster also plays a huge role in the Blackest Night story arc which I feel is one of the best.
Barry is also being portrayed in the new tv series The Flash on CW which has received quite a bit of praise. It shows a lot of his nerdy science loving side which you can't help but love. His detective skills help solve crimes and help him stop the villains in what is turning into a great show and an example of how awesome this character can be.
#4 Wolverine/The X-men
The X-men comics have an effect like no other. They show how terrible discrimination can be and how big a problem it has been and still is in the United States, and world for that matter. Mutants are hated so much that they are hunted down like animals. The message of these comics has a power like no other and they have one character like no other as well, Wolverine.
Wolverine is the definition of a badass. He walks the line between hero and antihero, and who doesn't love a good antihero? He has regenerative powers that make him near invincible and ages slowly making him near immortal. The man fought in nearly every war and has even gone to hell and back. While reading some comments on here one person said anyone who doesn't talk about the scene where Wolverine fights Nitro in Civil War should lose and he had a point. Wolverine's skin and muscle are tore away leaving almost nothing but adamantium. As if going to hell isn't enough. He is the character everyone would want on their team. He has been a part of the X-men and the Avengers and should be on any Top 5 in my opinion.
Batman is quite arguably DC's greatest character. He takes on some of the most iconic and devious villains as well. Batman has also changed more than any other character through history in my opinion. The picture above shows the original gray and blue suit to the modern all black one used in many of the movies and shows. Batman in the 1966 movie and television show was so quirky that it was comical and recent adaptations of the character are much much darker.
The one thing that remains is the Caped Crusader's detective skills. In any version he is able to find a way to solve the problem. When they have to fight off an evil Superman in the video game Injustice, it is Batman who helps lead the fight for good. Batman's long history just adds to his greatness. It dates back to 1939 and has always been a huge hit. I can remember waking up on a Saturday as a kid to watch cartoons, drink my chocolate milk, and read my Batman comic so of course he is on my list.
#2 The Amazing Spiderman
The amazing webslinger has always captivated me for some reason. I love every part of the comics. From his early days figuring out his powers, to each villain he faces, to his relationship with Tony Stark, I've been hooked the whole time. He fights off some of the greatest villains in comic history like the Green Goblin, Venom, and Carnage. He becomes highly sought after by the Avengers and is easily one of the biggest turning points in Civil War arc.
He has had several movie installments and even though they have been failures there is one reason they are able to keep trying, people can't help but love this character. Another thing he has going for him is the fact he basically has the catchiest theme song of any character. Anyone reading this just sang it in their head, admit it. There is something truly amazing about this character, and he will forever be one of my favorites.
#1 Captain America
He is the symbol of justice and patriotism. The soldier of not just America, but the world. Captain America is a born leader and a man out of time. A science experiment turned an "ordinary kid from Brooklyn," into everyone's hero. He takes on not only the Nazi armed forces, but Hydra as well. He sacrifices himself to save others being the noble person he is and is found in an iceberg decades later, but that doesn't stop him from stopping evil.
I hate to keep going back to Civil War, but it is one of if not the best story arc ever. Cap ends up becoming a fugitive as he doesn't see eye to eye with Iron Man and the government's policy to register their identities. It is hard not to take his side. He knows he needs all the help he can get but still goes off on Punisher when he kills villains that were going to help them. He shows he won't put up with anarchy even when he is a fugitive himself.
After his apparent "assassination" Stark even admits that he was wrong which makes you love Captain America even more. And he makes sure of all people to take up the shield while he is gone, it is his best friend and fellow soldier Bucky. Captain America is a role model as far as heroes go and will always be my favorite character.