If it's a bios password then you have a problem, Most laptops apart from samsung now use TPM - Trusted Platform Module - it stores the password in multiple places and can be a real headache to remove.
If it's the windows login password - use this
http://www.pogostick.net/~pnh/ntpasswd/
Instructions are on the site.
(Samsung laptops are a joke for security. Remove the memory cover and there are 2 solder pads marked 'RST' - short them with something metal and the bios password is gone.)