Hi, this may be when you discover disk imaging is a great way to back up your partitions or disk. I recommend Aomei Backupper. Disk imaging allows you to restore your PC or partitions exactly as they were when you created the image. And you can extract files from the images.
Now, Windows 8 does NOT allow you to do a repair install as in previous versions, sadly. So you can't simply reinstall Windows 'over the top' keeping everything else.
Nor can you get to Safe Mode in Win 8 by hitting F8 (not unless you had already used a well-known trick to enable it).
If you have a Win 8 CD/DVD (or an iso file you can burn one from) you can boot from that
Find the Startup Repair option, which will try to repair your startup configuration
You can also find your way to System Restore, and see if that helps.
Failing that, you may be forced to rescue what you can and reinstall. That's where partitioning can help somewhat- I try to keep as little as I can on C:\
Note that language packs are version specific- i.e. those for the same languages for Win 8 and 8.1 are different.