Files in your laptop or desktop computer would be lost if the PC crashes(for most after the Blue Screen appears !!)
You can use Backup all of the data on your hard disk to storage device, such as a hard disk or a tape to you protect your data if your hard disk fails or if you accidentally delete files.
Windows Backup Utility
Use the Backup Utility in Windows XP
SyncBackSE
SyncBackSE is a utlity to backup and synchronization the files, which also has Profile Wizard to create a backup or synchronization profile.