Windows restore is a wonderful utility for the protection of your windows.

How to use Windows System Restore effectively??

whenever you install fresh windows with all the required softwares.

Please check if every software is working fine  then you can create a restore point for that date.

name that restore point with a little description. so that you can recall it later.

windows will make a small registry backup for that date.

you can also create a restore point every week , or after every two weeks , depending on your work load and installations.

whenever you feel like that your windows registry is corrupt OR installed software are giving errors , OR you feel your system is getting slower , due to virus activities etc.  Now its the time to restore your computer to an earlier date when every thing was working very fine.