I have Windows Vista installed on my laptop. I install all the automatic updates. Recently Vista downloaded Service Pack 1 and I installed it. After the installation my laptop stopped working. I can only use BIOS now, Vista doesn't load. Only black & white menu appears with several options to choose (Safe Mode, Safe Mode with Networking, Safe Mode with Command Prompt, Last Known Good Configuration (advanced), Start Windows Normally) but none of them works.

Microsoft Support for Windows Vista (with no service packs installed) ended on April 13, 2010, while support for Windows XP (without Service Pack 3 installed) ended on July 13, 2010. Windows 2000 support ended on July 13, 2010 as well.
There is no Service Pack 3 for the 64-bit version of Windows XP. If you're running the 64-bit version of Windows XP with SP2, you have the latest service pack and will continue to be eligible for support and receive updates until April 8, 2014.
If you are still running a version of Windows where support has ended, it means that version of Windows will no longer receive any updates from the Windows Update or Microsoft Update site. These updates are generally provided for security reasons to help protect the PC from harmful viruses, spyware, malware, and other malicious software. Windows Update also provides new drivers for your hardware that can improve the reliability of Windows.
Hackers love to take a security vulnerability in Windows and exploit it to their advantage. So, if a vulnerability is found in Windows XP or Windows Vista and you are not running the latest service pack, you will not be protected and will be at risk.

How Can I Tell What Service Pack is Installed?
Follow these steps to discover what Service Pack is installed:
1) Click on the Start Button
2) Right-click on either My Computer or Computer (depending on your Windows version)
3) Click on Properties
On this window, it should tell you which version of Windows along with which service pack is installed). It should also tell you whether you are running a 32 bit or 64 bit version of Windows.

Where can I download the latest Service Pack for Windows?
For Windows XP, click on the following link to download Service Pack 3

For Windows XP Service Pack 3 info, click below :-
http://windows.microsoft.com/en-us/windows/help/learn-how-to-install-windows-xp-service-pack-3-sp3

For Windows XP Service Pack 3 download, click below :-
http://www.microsoft.com/downloads/details.aspx?FamilyId=5B33B5A8-5E76-401F-BE08-1E1555D4F3D4

For Windows Vista, click on the following link to download Service Pack 2

Windows Vista Service Pack 2 info, click below :-
http://windows.microsoft.com/en-us/windows-vista/Learn-how-to-install-Windows-Vista-Service-Pack-2-SP2

Windows Vista Service Pack 2 download, click below :-
http://support.microsoft.com/kb/935791

Introduction:
Windows Vista updates are distributed in service packs. Service packs
help keep Windows Vista current, and they can extend and update the
functionality of your computer. This article describes three
step-by-step methods that you can use to obtain the latest service
pack for Windows Vista. However, before you select the method that you
want to use, please make sure that the following conditions are true:
The service pack is not already installed on your computer.
You are logged on to your computer by using a user account that is a
computer administrator.
The computer on which you want to install the service pack is
connected to the Internet.
If you are not sure that all these conditions are true, please see the
"Before you try to download the latest Windows Vista service pack"
section. Otherwise, select the method that you want to use to download
and install the service pack.
Methods to download the latest service pack
Method 1: Turn on Automatic Updates (Recommended for most users)
Method 2: Check for updates on Windows Update (Same as Method 1 but
not automatic)
Method 3: Obtain the latest Windows Vista service pack from the
Microsoft Download Center (Good to use if the computer on which you
want to install the service pack is not connected to the Internet)
Important: Windows Update may not offer the latest Windows Vista
service pack to some users. This issue can occur for several reasons.
For a full list of causes and resolutions, click the following article
number to view the article in the Microsoft Knowledge Base:

948343 Windows Vista service packs are not available for installation
from Windows Update and are not offered by Automatic Updates