I don't know what is the problem with your windows 7 system. So, I just give one solution for the damage of C drive partition. If your windows 7 crush is caused by partition, you can use Easeus partition master to resize your partition, and restore your windows.

I always like pink.

Accidentally delete always happens, we need to take some measure to prevent important files losing from such action. I know a software named Easeus todo backup, it is a free backup software, and it can make an identical copy of your data. You can have a try, next time, be careful.

You need to download a driver program from the official website, I suggest you use some backup software to make a clone of it, for in the process of installation, there might be some accidents happen which will cause trouble to it.

You need a hard disk contain the windows system, then you can reinstall your system. But be careful don't make any mistake when your make a copy of the system to your hard disk. I suggest your use some backup software which can make sure the quality of cloned data.

You can restore your system to a previous time, but this action will take away the programs you have stored after this time. Another way is to reinstall your system, but you need to make a copy of your partitions, which may be a huge project, but I suggest you use partition software to guarantee there will be no damage of your previous data.