It's not a stupid question at all! Understanding which versions of Windows can be activated with a specific product key is essential. In your case, if you have a Windows 7 Home key but only have a Windows 7 Professional CD, you can still install Windows 7 using the Professional CD. However, you won't be able to activate Windows using the Home key as the product keys are version specific. Here's what you can expect if you proceed with this: 1. Installation: You can use the Windows 7 Professional CD to install Windows 7 on your computer. 2. Activation: When you try to activate Windows with your Windows 7 Home key, it will likely fail because of the version mismatch. Windows 7 Home keys are designed to activate the Home edition...