Speaking of backups, what about the all megabytes of patches and hotfixes that have to be downloaded from Microsoft to ensure to the security of its operating system?  If Windows is reinstalled all of those will be lost.

Can WinRescue make a backup of downloaded Windows system files? (and how do you find out where they all are, once installed?)

   Yes, all of them will be lost but they will automatically be redownloaded again too without the ones that are discontinued.
   Yes, of course, you can back them up with WinRescue.  They are in the Windows directory and begin with a $NTUninstall.