Yes, it could. It would set to the default values of your machine as shipped. Any changes made in the BIOS since then could be affected. If you can get in to the BIOS, print out the current settings ( values ) on everything or atleast write them down first.

Look in to the owners manual and see how it was set when shipped (Default). Then you can readily set it back up. But anytime you work in the Setup- BIOS , you should back up important data.

Don't know what else to tell you, don't know your OS, machine specs etc. From your description of the problem, I am not sure it is a BIOS password protection problem.

Did all this only start when you installed the CD-RW ?