To unlock your laptop using the easiest method available go to: http://dell-inspiron-1150-bios-password.biospwd.com
Dell password authentication system explained :
The BIOS of most modern computers also allow a password to be set for each of the connected hard drives. This password is stored in the service area of the hard disk. Because of this, moving the password protected hard drive to a new computer does not allow access to the hard drive unless the password that was assigned to the hard drive is provided.
The ATA Security Mode Feature Set that is implemented in all modern hard drives actually provides for two passwords, a "Master Password" and a "User Password"
The User Password locks the hard drive and the Master Password is only used to allow an administrator to reset the user password.
The BIOS of many computers will not allow the master password for the hard drive to be changed from the default, so they rarely are. A quick search of Google.com for the specific model of hard drive with the phrase "ATA Master Password" will generally result in multiple web pages that contain the default master password . Hardware tools can recover, reset, or brute-force both the User and Master Passwords.
Full Disk Encryption Methods:
There are two major categories of full disk encryption (FDE)-software-based and hardware-based. Software-based encryption modifies the hard drive drivers and uses the CPU to encrypt all data as it is written to the drive and decrypt all data read from the hard drive. Hardware-based full disk encryption is built into the hard drive and is totally transparent to the user and does not impose a performance impact on the computer.
Software-Based Full Disk Encryption
Wikipedia maintains a lengthy list of disk encryption software The two most popular FDE software implementations are TrueCrypt and BitLocker. BitLocker is included as a feature in the Ultimate and Enterprise editions of Microsoft Windows Vista and Windows 7, but has to be enabled and configured to provide protection. TrueCrypt  is free open source software that is ideal for individual users, but lacks management features that make it attractive to enterprise-wide deployment.
Deployment of software-based full disk encryption in any organization with more than just a few computers requires careful consideration of how the encryption keys will be managed. Great encryption without proper key management is like locking the doors to your house and leaving the key under your doormat. One study on the usage of encryption states that 54 percent of respondents had experienced either stolen or unaccounted for encryption keys and that 78 percent experienced system downtime due to encryption failures in the past twelve months . Full Disk Encryption solutions that are targeted at the enterprise typically offer integration with Microsoft's Active Directory or other LDAP directories for secure key management.
In 2008, security researchers created shockwaves by publishing a paper called Lest We Remember: Cold Boot Attacks on Encryption Keys . This paper, and the accompanying YouTube video demonstrate how Software-Based FDE can be circumvented by rebooting a computer that has been left in a locked-screen or sleep state. The attack exploits the fact that Dynamic Random Access Memory