It is indeed the BIOS password that is causing the problems.

In that case follow the advice above and contact vaio supprt for a BIOS unlock code for your Vaio..

I will try and contact Sony via the link you sent, but last time I looked my model number didnt seem to be listed: PCG-6S3M 

the PCG-6S3M is not your VAIO's model number that is the chassis number..

If  you are not sure which VAIO model you own, possible a VGN-SZ series,   either login on the Vaio support site using option 1 using your Vaio's  serial number..

The serial number can be found on the underside of your Vaio..

Or

Your actual VAIO model should be shown on the lower right hand corner of your screen's surround..