The simplest option would seem to be finding the password written on the chip of the laptop-motherboard.
Another rather simple solution that can be applied to some Dell laptops would be:
- go to BIOS (shut down your computer, press F2 when it starts)
- scroll down to "Security" in the left-hand column.
- press arrow right to access a sub-menu under Security in the left-hand column.
- press arrow down to "Internal HD PW" in the left-hand column. (That stands for Internal Hard Drive Password.)
- delete the old password (if any) and enter a new one
- press Enter.
- press the Escape button on your keyboard to exit to the Internal HD PW menu, then press Escape again to proceed to the Exit screen of the BIOS Setup.
- press arrow right to save the changes you made to the password, then hit Enter on your keyboard to exit the BIOS Setup.
- reboot your computer and use the password you created in the BIOS Setup to gain access to your hard drive.
The other options are rather costly or complicated, hope one of the easier ways will work.