OK.There are 3 places from where you can remove EVERYTHING YOU DO NOT NEED:
1. If you are using Windows XP or newer,(and even some older OS then XP),go on this location:
C:\Documents and Settings\YourUserAccount\Start Menu\Programs\Startup\
From that location remove EVERYTHING you do not need.For example...you can remove ALL programs that you do not use,but are raising on Windows startup.BE SURE NOT TO REMOVE YOUR NETWORK PROGRAM WHICH IS NEEDED TO BE ABLE TO GO ON THE INTERNET AND SOME PROGRAMS THAT ARE PROTECTING YOUR COMPUTER FROM VIRUSES!!!
2. Open the Registry Editor by writing "regedit" in the RUN program or by going into the WINDOWS folder and open the file called "regedit.exe".On the left side inside of that Registry Editor program there is going to be a small tree which contains few HKEY values.Now go on the following location inside of that registry:
HKEY_LOCAL_MACHINE\SOFTWARE\Microsoft\Windows\CurrentVersion\Run\
Inside of that "Run" registry section you have many string values.So here take a look at everything you do not need and delete it by going right click on it and then "Delete" and when it asks you if you are sure that you want to delete that registry value,click "Yes".
NOTE: BE CAREFUL WHAT YOU WILL DELETE BECAUSE IF YOU DELETE SOMETHING WRONG,YOU CAN DESTROY YOUR OPERATING SYSTEM!!!!!!!!DO THIS ONLY IF YOU ARE 100% SURE THAT YOU KNOW WHAT YOU ARE DOING!!!!!!!
3. The third way is of course the System Configuration Utility or so called MSCONFIG.From the "Startup" tab uncheck ALL the programs that you do not use.BE SURE THAT YOU DO NOT UNCHECK THE DRIVERS!!!
You can also turn off the automatic updates from the System Properties on the "Automatic Updates" tab...Trust me you don't need this unless you want your computer to always have the newest updates what is a bad idea because sometimes it can destroy your OS by installing bunch of unneccessary crap.
RECOMMENDATION: Install ONLY THOSE updates that you need.Do NOT intall the updates that you don't need!!!
Also turn off the automatic updates check and automatic updates installation on ALL your programs.
RECOMMENDATION: Update your programs ONLY if you need to or if the updated version has some features that you need and the old version doesn't have them!!!
After all this,execute the DISK CHECKING process and then defragment your HDD.After that clean up all invalid registry by using the program called "Eusing Free Registry Cleaner 2.0" or newer version...
After you have done all this,your computer will work much faster unless your hardware is 100 years old.
...you might uncheck something that's important and it can cause your computer to run unstable.
Exactly!