Windows Vista, the next generation OS from Microsoft is now RTM. This DVD includes both the 32Bit and 64Bit versions of Vista on 1 DVD. It is bootable into either the 32Bit or 64Bit setup and will allow you to install any of the versions of Vista listed below:

Windows Vista Home Basic (x86) or (x64)
Windows Vista Home Basic N (x86) or (x64)
Windows Vista Home Premium (x86) or (x64)
Windows Vista Business (x86) or (x64)
Windows Vista Business N (x86) or (x64)
Windows Vista Ultimate (x86) or (x64)
Windows Vista Starter (x86)
 

You can also install Vista from another Windows via the autorun. However please note that you cannot install/start the x64 Vista setup from a 32bit/x86 Windows install, you must start it from an x64 install of Windows.

OEM/Retail versions are all available on the DVD depending on the type of key you enter.

Similar to our previous releases of Vista during the beta, we are providing 1 key that will install Vista. In this case, the key is an RTM universal key and will allow you to choose whichever version of Vista you wish to install. The key will however not activate Vista. The same key is also builtin to every Vista ISO by MS for trial/quick install purposes.
For further info, see \sources\x86\sources\inf\setup.cfg on the ISO.

Therefore, that means you can also choose to install Vista without a key by selecting Next during the cd-key prompt during Setup without entering a key, then pressing No for the popup window. It will make no difference to activation however and you will still have a limited period of time to use it.

Since Windows XP, Microsoft has instituted Windows Product Activation (WPA). This prevents any extended full usage of the Product beyond the allotted time, determined at install. We are NOT providing workarounds or 'fixes' for WPA. You are still required to activate your software within this time. While we are aware of possible workarounds in the wild that may work with Windows Vista, we suggest keeping yourself out of trouble. Most release groups will tell you, "if you like it buy it," we say the same