security tools boot disk

Dear List,

This is my first post.
I tried to look for a way to search the archives but I couldn't find a way.
I'm sorry.

Basically I want to create a "small" Linux boot disk that will contain some security tools (audit, packet analyzer, etc).
I just don't know which Linux distribution to use and which tools that are offered for that distro. that I should use.
Basically does anyone have a site that shows how to make such a disk?