open the task manager and in the process tab click on explorer.exe and then end task then go to file and select new task and enter explorer.exe by this your systeme will be refreshed then go to start button and in the search write system restore and enter after this select a date (try to select a date at which your laptop was fine) then leave it to complete the backup (it will take about 5 to 10 minutes) and after that it will restart and your laptop would be back to normal