If your response is limited to only an analysis of the three characters mentioned in your posting, then I would say no, there is no evil in these characters. They each have there flaws, but their ultimate intentions are not malicious, premeditated or evil.
We know very little about the life and actions of King Hamlet, but he seems to have been a good king and a successful warrior. He lawfully engaged in a battle with King Fortinbras, won, and gained land as a result. This is not evil, this is just a matter of life in these times. It is what kings did in order to secure their kingdoms. His return as a ghost isn't evil. He needs to have Prince Hamlet know that Claudius murdered him and ask for vengeance. Hamlet feels a need to assure himself that the ghost is a "true" ghost and not a devil in disguise, but once that is done he is free to act. Seeking vengeance isn't considered evil -- it is an act of justice.
Polonius isn't evil; he is a conniving, sneaky spy, but he isn't trying to cause permanent damage to people. He wants to protect his and his family's reputation and prove himself important and valuable to the king. His spying ways result in his accidental death by Hamlet.
Hamlet himself is not evil. He is actually extremely cautious about committing acts that would be considered evil. He verifies the story of the ghost by getting proof that Claudius did, in fact, kill King Hamlet. He doesn't kill Claudius when it appears he is at prayer. He accidently kills Polonius thinking it is Claudius who is hiding behind the curtains. He rewrites the letter to England as a measure to save his own life, not to unjustly have Rosencrantz and Guildenstern killed. He stabs Laertes with the poisoned sword only after he was struck by it first, and even at that moment he doesn't realize the sword was poisoned. He does kill Claudius, but that is the act of vengaence that he has been struggling to complete through the whole play.