Windows 7: Reinstalling Win7 Can I backup current ProductKey & Activation?

Hi
After attempting in vain to install IE9 beta. My windows is playing up and cant install anything now.
I get "The resource loader cache doesn't have loaded MUI entry" error
I have tried SFC /scannow but nothing. And I do not have any "System Restore"

now the "Turn Windows Features" Winds is blank and I think I need to repair or Reinstall the Windows 7.
I have DVD and Serial Key "however when last time I installed Windows 7 it did not accept my Key and I had to call and the customer give me the activation code.
Now If I reinstall I am not sure it will accept the key again and I may need to call them again.
My question is "Can I backup my Current Product Key and Activation"?

If you do not have a backup of the OS and you want to reinstall, you must validate in the normal fashion. It can be by phone or during the activation process. When validated this time, with the free software that is available or even the native system image, make a backup, you will never need to validate again.

Run a Repair Install . Don't worry about reactivation, at most it will require a quick call to MS when reactivating at Computer>Properties link. You own Windows 7 for life and it cannot be taken back for any reason.

Why is System Restore not working? This is where it is needed and a Restore Point should most definitely have been set.

Thanks

You are right I asked because I installed this Windows 7 on 3 laptops as it is licensed for 3.

So definitely I'll have to call again and give then that was it 16 or 24 long numbers.

Sys restore is not available cos I disable it following some silly guidance before to speed up my net book

I think I'll make an image this time after doing a fresh reinstall..

Tweaking is not needed in Windows 7 and will almost always come back to bite you.

If you have issues then bring them here for help resolving them.