Install linux from within windows 7

I have an old Windows 7 Toshiba Tecra A9 with a locked BIOS which won't let me boot off anything but the internal hard drive. I sadly lost the BIOS password a long time ago. I am however administrator on this machine. Is it possible somehow to replace windows by linux in such a situation?

You can use wubi https://wiki.ubuntu.com/WubiGuide or you can try to remove the password by using http://thegeekdaily.com/easily-reset-bios-password-with-pc-cmos-cleaner/ or by taking apart the laptop and removing for a few seconds the cmos battery.

Real nice solution. Are you familiar with PLOP?
http://www.howtogeek.com/howto/16822/boot-from-a-usb-drive-even-if-your-bios-wont-let-you/
Just download it and save it then you need EasyBCD
http://www.filehorse.com/download-easybcd/
Then you should configure EasyBCD to boot from your iso file

Then you should be able to see a new option on boot. Enter it and you will something like this:

Which enables you to boot from anything you like. CHEERS!