It is an operating system and it is absolutely legal be sure. I also like
GoblinX. I would recommend you Slax www.slax.org NimbleX or Puppy Linux as live
CDs, they are very interesting and yes, you can access the files on the hard
disk no matter what operating system is installed on the PC and these live CDs
are wonderful tools for file recovery (to copy files out of a PC). Slax can even
be loaded into RAM if there is enough (most probably there is). For everyday use
I recommend Ubuntu or an Ubuntu derivative.