How to restore windows 7 to original factory settings ?

It is a partition on your hard drive which contains all of the data and code needed to set up Windows 7 just as it was when you first bought your computer..

You should save all of your important stuff before starting the process..

Your computer has been supplied with a recovery partition in place of disks..

This is how the recovery partition is accessed for the most popular makes..

For Dell, press CTRL + F11 directly after powering up the unit

For HP, press F11 directly after powering up the unit

For LG, press F11 directly after powering up the unit

For Toshiba, press and hold '0' BEFORE and during the power up

For Acer, press and hold ALT + F10 as soon as you see the logo

For Asus, press F9 as soon as you see the Asus logo.

For Samsung, press F4 at power up..

For Fujitsu,  press the F8 key repeatedly directly after powering up

For Advent, restart your computer. Then Press F10 repeatedly until the message "Starting System Recovery" is displayed

For Sony VAIO, restart and press "F8" or "F10" repeatedly until the "Advanced Boot Options" screen appears.

You may have to try more than once to get any of the above to work. If after repeated attempts, you have no luck or the machine reports that there is no recovery partition, your only option is to contact the computer manufacturer and ask for recovery disks for the model.. 

After the reset, you should get all updates from Windows Update EXCEPT for hardware devices. Next, you should install a good anti-virus solution. ONLY AFTER you have done this should you replace stuff from backups or install anything else.