When you register Windows, you're giving Microsoft your personal contact information. You do this in case you have issues and so you can receive updates and offers (this is optional).
Activation "unlocks" Windows and shows Microsoft that you are using a genuine copy of the OS (this is NOT optional).
Here's a link with the official explanation from Microsoft...
If it prompts you to do so, I probably would. Although, if you did it the first time you installed the OS I'm sure Microsoft has your info saved on their servers regardless. It's completely up to you.
Giving it second thought... I would register again. If you don't, Windows will probably annoy the crap out of you until you do. So, yes, register again if prompted.
Giving it second thought... I would register again. If you don't, Windows will probably annoy the crap out of you until you do. So, yes, register again if prompted.
Very interesting. I've always gone through the registration process. So, I was just going on an educated guess that Windows would have a "nag" window pop up once in a while.
Yes, corporate copies of Windows don't need to be activated. In the computer lab at my college, we installed XP on about 20 machines with the same registration key.