Step 6 : Now uncheck those softwares or applications which you dont need . For example : In the screenshot above i can uncheck winamp , quicktime , MSN messenger etc because i dont need them at startup . Dont get scared that you would screw up your system if you uncheck something important , incase something is not working after you unchecked some software, then just put the tick mark again the next time you boot .
Step 7 : Services like your antivirus software ( avg in this screenshot), any other drivers ( like asus drivers) etc should be left ticked as it is required for them to load at startup. Frankly speaking even if you uncheck all boxes and restart nothing will happen , your system would boot fine , infact it would boot real quick . So dont worry if you uncheck the wrong application , you could always tick it back the next time you boot.
Step 8 : Once your done unchecking the unwanted softwares . Click on Apply and Click on Close
Step 9 : You would then get an option to Restart Now Or Later . Thats your choice actually , but changes will take effect only after you restart.
Step 10 : Once rebooted , I'm sure it would make your system a lot lighter and a Lot more efficient!!