Hi,
before reading this post, please take a look at this one:

linuxquestions.org/questions/history/85636

Now,
when im trying "vi /etc/inittab" i get a screen with nothing, just a colum with "~".
so I there's no "id:5:initdefault:".

Second,
How do I exit that file?
when i press ESC and type exit, after i press the "i" button, it writes the rest of the word.

Please help,
Thanks.

Hi,
I have read the thread that you listed. I do not know what distribution you have, but it is possible that it may not work for you. I, for instance, have nothing under /mnt, so I do not believe it would work for me. BUT, I am not sure.

I am editing this part - I have read the post that you asked be read. I may have completely misunderstood. If you boot into a blank screen, and are able to get to a command prompt, but it does nothing, then the following will be of no benefit to you. - end of this edit (I think this makes four)

If you are able to boot into linux (even a blank screen), you might try the keys <ctrl,alt,F1> and see if it takes you to a command prompt. If it does, and you can log in as root, try the <vi /etc/inittab> command from there.

Usually when you get a screen full of ~ as you describe, it means you are in the wrong place. I "think" it means that the vi editor is trying to create a file by that name for you. To exit from this, type (esc, : , q, ! , and then enter). This should drop you back to a prompt. This is a good sequence to remember when you are editing a file, and get confused and lost (and you will). It will drop you out of the file, and leave it unchanged. Then you can start over.

If you successfully edit the inittab file, and want to save the changes you have made, then the sequence would be ( esc, : , w, q , and then enter) to exit.
Good luck