USB booting :: Quick first time question
i mounted the harddrive and looked around, then copied some files from my thumb drive back and forth. nothing happened, but i didn't mess around with the windows files or programs. everything still works. very cool.
1. yes, there is a way to save your changes with DSL. DSL includes a manager that allows you to backup your settings, history, bookmarks, etc to any sort of storage that you have.
2. There are differences between different distributions of Linux. The differences are mostly in the the way they are installed and the types and ways that application programs are packaged. Some distributions also use slightly different ways of booting up. However, the core of the operating system, which is Linux, is basically the same.
3. What he said. But give it a try with the live CD first. Version 1.5 is very fast right off the CD and you can still back up settings, etc. to a USB pendrive if you like. 
original here.