Ever notice the way Polonius is always yammering on and on? The guy really loves to talk – he dishes cliché advice to his son, Laertes, before the kid heads off to college ("to thine own self be true," "neither a borrower nor a lender be," and so forth), and he often speaks in an overly ornate way when telling stories. Even the ever-gracious Queen Gertrude has to cut him off at one point by saying "More matter, with less art" – that's code for "cut it out and get to the point."
What does this say about Polonius? He's a bit of a buffoon and kind of a poser. He wants to be taken seriously but he ends up coming off like a foolish old man. As it turns out, Polonius doesn't stand a chance in the highly competitive and political world of the court. (Eventually, he gets himself stabbed in the guts when he tries to spy on Hamlet.) King Claudius, on the other hand, is a guy who knows how to talk. He delivers well wrought speeches that are in keeping with his deceptive nature.
Though yet of Hamlet our dear brother's death
The memory be green, and that it us befitted
To bear our hearts in grief and our whole kingdom
To be contracted in one brow of woe,
Yet so far hath discretion fought with nature
That we with wisest sorrow think on him,
Together with remembrance of ourselves. (1.2.1)
The speech starts out by acknowledging Old Hamlet's death and the grief felt by the entire kingdom but check out the way Claudius manages to sweep Old Hamlet under the rug when he says it's time to move on from all the boo-hooing. Basically Claudius is saying something like this: "It's fine to think on Old Hamlet with sorrow but, at the same time, we should do that "with remembrance of ourselves." Yeah. We almost didn't catch that last part either. Claudius is pretty crafty, which is why he's got everyone (except Hamlet) eating out of the palm of his hands. It's no wonder Claudius has talked himself into being elected king by the noble council. It's also no wonder Claudius scored himself Queen Gertrude, the wife of the brother he murdered.
For some characters, actions are pretty straightforward markers of character. King Claudius, for example, is easy to figure out. He kills his brother, only to help himself to his dead bro's crown and wife, which clearly makes Claudius a bad guy with no morals.
Hamlet's actions, on the other hand, raise more questions than they answer. Why does Hamlet pretend to be a madman? Why does he abuse Ophelia? Why does Hamlet delay killing Claudius? Let's think about the last question for a moment. Hamlet is unlike any other revenge tragedy hero in that he delays avenging his father's murder for a looong time. But why does he do it? We don't know for sure. What we do know is that while Hamlet is not killing Claudius, he spends a whole lot of time thinking, which alerts us to the fact that he's introspective, philosophical, and deliberate. Most of the time. Fortinbras and Laertes, on the other hand, are polar opposites of Hamlet where actions are concerned. They're both swift to take steps toward avenging their fathers' murders.