|What u want is to restore your laptop and this can be done if the laptop have recovery partition or disks. If not u have to find the OS disk (bootable copy of win vista or 7 etc).|
Make sure to put your stuff in a safe place (external hdd or data partition) because restoring or installing OS from scratch will erase all the contents in drive C.
Finally necessary drivers and utilities must be installed to make your life easier.
You know the real meaning of peace only if you have been through the war.