Get a good imaging program.
I use Macrium Reflect (free home use version) to image my C (operation & programs drive) and D (data partition).
Restoring images has saved me many times.
Reflect allows you to create a bootable disk (Linux) and save images while actually in Windows.
I save my images to a USB 3.0 drive. It takes about 40 minutes to image and to restore my C drive.
http://www.macrium.com/reflectfree.aspx
Imaging comes in handy when a regular System Restore won’t work.
I create image files a couple of times per year and after major installations or upgrades of existing programs.
When I messed myself up, I could not even get to System Restore. I finally booted in Safe Mode and got to Setup where I was able to revert to a normal startup and that fixed the problem.
I second the recommendation regarding Macrium Reflect. It’s great software with excellent support. I never worry about data loss.