Queried: "current I use Fedora Linux in USB stick, can I possible log on as root user via terminal command, what is the command please?"
If it boots you can certainly log on, as a user or root.
Pressing Ctl+Alt-F2 (F3, F4, F5) will open you a tty terminal with a login prompt, there you log in, using your name and password. If "root" account is not enabled you may login as a User then enter command: su <Enter> give password for root.
You can do google for tutorial, or download this tutorial in my signature below, read first the basic ideas for Linux system (not all at once) then you will feel confident to solve your problem. For any problem that may come later you can browse over the tutorial, open xpdf, press Ctl-F then enter word you wanted to search, using this tutorial is easy if you know how to search on it.
Hope this helps.
Last edited by malekmustaq; 08-13-2009 at 08:40 AM.