Claudius
In doing an analysis on Claudius, I found him to be a man without a conscience when dealing with all his secrets. He seema to make decisions quickly and doesn't consider the consequences involved. Though, I admit some of his ideas are clever in a sadistic way. At times it's almost as if his methods for solving a problem, like Hamlet, only make the problem worse.
All his secrets involve close family members, whether biologically or lawfully related. His major secret is him killing his own brother for the crown and possibly for his wife as well. Maybe his motivation was out of jealously or even revenge because of favoritism by his parents. His other little secrets deal with Hamlet's attitude towards Claudius, Gertrude, Ophelia, and even Polonius. After "moving in" the castle Hamlet has been nothing but problems for Claudius. So, a majority of his time and energy is spent on "figuring out" what's bothering him. Whether he's doing it because he may actually care or because he fears Hamlet may discover his secret we're not sure. It's made a little bit clear when Claudius goes to the play and realizes Hamlet knows.
In Act II Claudius gives the permission for Polonius have Ophelia give her gifts back to Hamlet. Polonius is the one who informed the king of what Ophelia had told him about Hamlet. When the king finds out about this it's almost as if he plans to use it against him. To me it seems as is he wants to ruin Hamlet's 'status' in the castle, of a "love sick pup" or as a person gone mad.
He could use Hamlet's "insanity" as a way of nstregthening his trust with gertrude, so if Hamlet happened to make any accusations on the king, Gertrude wouldn't believe him. His determination to help Hamlet also, could cover up his major secret even more. Maybe this will achieve a possible goal of his, or help him enjoy his "rightful"