Having more than ten 'Linux Live' in a single MultiBoot DVD or USB media was impossible but for geeks.
Now with SARDU this is available to everyone with a few clicks and without any knowledge.
There are live distributions which focused on security and penetration testing like as BackTrack (able to test and crack the wifi) or others with a software suite used for hardware diagnostics, stress testing, certification and benchmarking platform like as Inquisitor or Phoronix Test Suite.
With Limp (Linux Multimedia Player) you can transform your PC as multimedia player. This offer a better interface to play all Video and Audio formats.
You can start and use complete distributions like Fedora, Kubuntu and Ubuntu, Linux Mint or YLMF. This way you can find an easy way to approach Linux.