Computer security/privacy is a process, not a product. As snowpine said "The answer likely depends on who is out to get you, and what tools they are using to spy on you." Decide what level of security/privacy you're looking for, and take it from there. Search for such things as "hardened Linux" for more info on how to go about this.
Edit: Having said this, I use OpenBSD, because of their focus on clean code and security.
Last edited by JWJones; 03-07-2014 at 06:34 PM.