Need help restoring Windows 8 Single Language and updating to 8.1

Question

To cut a very long story short, I have 2 PC's from different manufacturers. One is mine and the other is a friend's. Both came with Genuine OEM Windows 8 Single Language preinstalled. When attempting to update my PC to 8.1 from 8.0, it failed to boot so
I took it my vendor. They tried restoring 8, which involved wiping the HDD (incl. the recovery partition) and when they failed they installed a pirate Windows 7 and accused me of "messing" with the system. They voided my warranty :'(
I made a Recovery USB. My PC boots to it but refuses to install. Says "A required drive partition is missing" (Probably the recovery partition).
So then I came across the idea of making an image from my friend's PC to install on mine, after "generalizing" his PC: ("The Sysprep /generalize command removes unique information from a Windows installation so that you can safely reuse that
image on a different computer.")
Source: Capture an Image for Deployment (Generalize)
http://technet.microsoft.com/en-us/library/hh824938.aspx
But I still have some questions:
1. When my friend's PC makes the image, will I be given the option to decide the file's location (such as creating it on an external HDD)? If not, where will I find it if I boot the PC in a live environment (such as a Windows setup DVD or Ubuntu LiveCD)?
2. How large is this image (in GB)? Can I split it? 
3. After completing, how do I "undo" the generalization on my friend's PC so it goes back to normal?
Any help will be greatly appreciated.
PS: To Mircosoft: Please consider making the Windows 8/8.1 Single Language ISO available for OEM customers to download in case of problems. This will help us avoid these complex techniques.
Thank you.

Answer 1

If the system was reinstalled with a pirated version of Windows 7, the piracy can be
reported here to Microsoft.
For installation media for a system which was preinstalled by an OEM, the system manufacturer will need to be contacted. The operating system can also be installed from standard OEM or System Builder installation media if you have access to such media. If
the product key is embedded in the system firmware, the Windows installation will be able to use it.
For future reference, it is possible to include the recovery partition as part of the USB Recovery Drive, for which
the steps are available here from Windows Support. Similarly, the System Image Backup functionality from previous versions of Windows is also still available and
documented here on Windows Support.
Brandon
Windows Outreach Team- IT Pro
The Springboard Series on TechNet