christianj,

First you must have a copy of the operating system CD. See this post for details.

Once you have it, the procedure for correcting the error you are receiving (and the procedure does not work all the time) is here. In the meantime, since your system was probably made after July 15, 2004 you can restore it to "as shipped" condition (you would lose anything you have added to the system since you received it if you do this) using the procedure here.

Thanks, the ctrl-F11 method worked out fine!

My second problem is also during startup: "Floppy diskette seek failure. Strike the F1 key to continue, F2 to run the setup utility."

It works fine when I press F1, but I would like not to receive the message...