Physical abuse or corrupt files can cause a system to crash, but even though a system crash makes a computer behave erratically, there are several solutions you can use to fix the problems.
The System Restore utility saves snapshots of the system when everything is working fine, and these snapshots can be recalled any time a system is having trouble. The utility also lets you manually take these snapshots, called restore points, at any time, so you can preventively protect your system from potential crashes.
If the System Restore utility is unsuccessful, you can use the Windows installation CDs to repair the current Windows installation. Doing so maintains all your current applications, settings, and data files. As a last resort you can reinstall Windows to a blank hard drive folder.