Question: I have a Toshiba laptop with Windows Vista Home Premium installed. And I'm considering an online upgrade purchase of Windows 7 Ultimate. The site's description of the product reads:

"Microsoft Windows 7 Ultimate 32/64 Full Version /or Upgrade. Already activated no key needed. You don't even have to have an operating system just insert DVD."

Is this legitimate? I thought one always needed an activation key along with the Operating System hardware.

Answer: 
If you are buying an upgrade from the manufacturer, then this is legit. Any other reseller, then I'd hesitate without verification from the OEM.

The no activation is part of Microsoft's agreement with OEMs that allow them to install Windows on their hardware without having to type in a key. A combination of specific hardware and software allows them to do that.

Which, again, is why I'd make sure it was through Toshiba and no one else.
Beware of all Craigslist ads which offer any PC for sale with Windows 7 "pre-installed" for under $120! A retail copy of Windows 7 alone still costs around $100. Be especially leery of it is an older PC designed for Windows XP and be wary if the same dealer is selling several of them. In order for such dealers to make any money at all, the copy of Windows 7 is almost certainly pirated! If they aren't including a Windows 7 COA (certificate of authenticity), it is probably pirated. The computer may appear to work fine when the person sells it to you, but you will likely either run into problems 30 days from now when the "trial period" expires, or when you attempt to install updates from Microsoft.