Yes, Safe Mode.
When you have a major problem like this, the first thing you need to think about is preserving important data.
Do you have any important documents or pictures on that computer that you need to save? Assume the worst, that your Windows is infected, or damaged beyond repair.
In the worst case you will have to do a clean Windows reinstall and you will lose all your data.
So, the first thing you need to do is preserve any valuable data: have a copy of all important files.
(Not programs, as they might be infected, just data files).
When I face a situation where I need to reinstall a laptop from scratch, I usually use it as an excuse to upgrade the hard drive. What I would do in such case, I would replace the hard drive with a new one (rather easy to do on most laptops), do a fresh Windows install on the new hard drive, and put the old drive into a USB enclosure (inexpensive enclosures can be purchased at a local Micro Center store or online). This makes it easy to copy old files from the old hard drive to your new installation. And after all is set and done, you end up with an external drive, which you can reformat and use for backups.
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