How do we prevent terrorist from hacking into computers? Should we have the right to monitor the internet to see if people are radicalized? Should we issue the death penalty to terrorists? Should we torture captured terrorists to get information? Where should terrorists be tried? Should we have the rights to go to other countries and kill terrorists?

While I cannot provide you with your own opinion, I can at least share some thoughts on the subject in order to help you formulate your own ideas.  One of the main ways to stop terrorists or agents of foreign governments from hacking into computers is to prosecute webmasters; however, this only provides security after the damage has already been done.  There is anti-virus software and encryption technology out there to keep computers safe, but there is a race between hackers and security experts.  Computers may truly never be safe from terrorist hackers or from those who hack for other reasons.  
Internet monitoring has been a key issue, especially with the spread of radical websites and terrorist propaganda.  However, that is a slippery slope, as some claim that the same laws used to prevent terrorism online can also be used to clamp down on free speech.  One can find any message he/she wants on the Internet; it is up to each and every one of us to be responsible users of media.  Government intelligence experts can track terrorist organizations through websites in order to defeat them at their source; however, this also opens questions about the potential of the government using that same technology to pry into its citizens' lives.  
The Global War Against Terror has opened a Pandora's Box in terms of legal issues. On the international level, "enhanced interrogation techniques" are generally considered to be torture though the U.S. has, in the past, maintained that they do not fit the legal definition of torture. In the U.S., many argue that since many terrorists are not U.S. citizens, they should not benefit from the laws protecting U.S. citizens.
 I will now offer my opinion on this using historical precedents.  Centuries ago, Britain led the way in defeating piracy in the Atlantic and Caribbean. In many cases these pirates were non-state actors--similar to terrorists today. Some of these pirates were British citizens; however, many were of other nationalities.  These pirates were tried in Admiralty courts and often hung.  They were not tortured any more than any other defendant in order to gain information on other pirates.  I believe the U.S. should take a similar approach.  Terrorists should be captured and given swift trials instead of being detained in black sites.  They should not be tortured, as torture is ineffective and destroys the U.S.'s international human rights reputation.  The U.S. should strongly encourage other nations around the world to join together against terrorism and provide a united front against non-state actors who threaten world security.  The U.S. should not use drone strikes or combat troops in other nations without the permission of that nation, as the U.S. would complain if that other nation used troops or drones to go after terrorists in this country.