windows protection error please...

friend,
i have unknownly a error occured after starting the pc as :

"windows protection error. You need to restart your computer."
after this statement if we restart the computer, it again gives the same error and halt.
secondly it does not detect the CDROM so that if we try to reinstall the windows98se for repair.

please waiting for the urgent solution help please.

adj

hold down the control key while it is booting (for newer OS's)
to boot up in SAFE MODE. This will start up the system with no drivers. It is then up to you do figure out which driver is causing the problem. It could be something as simple as starting with the wrong screen resolution.
Post again to get further suggestions.

:D