I have been using True Crypt on my external hard drive for the last 18 months and it was the best choice ever. Setup is not complicated at all, the help file provides a walkthrough to encrypting the whole drive / part of the drive. You just have to decide on the encryption algorithm alone, just do some research on the subject, should not be a problem.

The best feature is that there is absolutely no speed decrease while using True Crypt. Absolutely recommended.

I have been using Hamachi for some time mainly to play games over the Internet with some friends that only support LAN multiplayer. Sure, it works with all pirated games as well with the main benefit that the key of the game is not checked on a central server because the game thinks it is a lan game.

I would definately use ftp instead of Hamachi for sharing some files with your friends.