Check is running wampserver.
At the first download wampserver, then install it by following guide.
You can save shop database.
You can keep all shop database and source code by saving wamp folder.
If you forgot the admin password, you can recover it by following guide.
If your windows do not start, but you can get wamp folder with all files, then you can recover the application with database.
It can be mysql database problem. And there is way to recover the mysql tables.