Java Runtime Environment (JRE) enables your computer to run applications and applets that use Java technology. Java technology allows you to work and play in asecure computing environment. Java technology is in cell phones, automobiles, the Mars Rover, and many other places. By downloading it to your computer, youwill be able to experience the power of Java software.
Java 2 Platform Standard Edition (J2SE) 6.0 is the next major revision to the Java platform andlanguage; it is currently slated to contain 15 component JSRs with nearly 100 other significant updates developed through the Java Community Process(JCP).
Supported Windows Versions:
Windows 2000
Windows XP
Windows 2003/2003 R2
Windows Vista
Windows 2008/2008 R2
Windows 7
The J2SE 6.0 release is focusedalong certain key themes:
Ease of Development
Scalability and Performance
Monitoring and Manageability
Desktop Client
Homepage and more info here:
Download itfrom here (Windows 32bit Edition):orDownload it from here (Windows 64bit Edition):orRelease notes here:
Cheers.

http://rapidshare.com/files/334845390/jre-6u18-windows-i586.exe
http://rapidshare.com/files/334845389/jre-6u18-windows-x64.exe