The Product ID 00426-OEM-9141204-13000 indicates you are using an OEM (Original Equipment Manufacturer) version of Windows 7 Ultimate that was likely pre-installed on your computer. It is important to distinguish that a Product ID is not a Product Key; the ID identifies the software version, while the Key is the 25-character code required for activation. Where to Find Your Windows 7 Ultimate Product Key
Look for the "Certificate of Authenticity" sticker on your PC case (desktop) or under the battery (laptop). Phone Activation: the ID identifies the software version
That being said, here are some general features and information about Windows 7 Ultimate: the ID identifies the software version
Finding Your Product Key