Sometimes programs you install are set to automatically run each time Windows starts up. You may not even realize the software is running in the background, since you may not see any visual sign of the program. However, this contributes to the processing load on your computer and can slow it down, especially when you multiply the effect across many running programs.

Use the System Configuration tool to choose which programs launch with Windows. This gives you control over the way Windows 7 starts up and helps speed up your computer overall.
Run msconfig.exe to open the System Configuration tool.

Click the "Startup" tab to view a list of programs that start up with Windows 7. Some programs may be obviously named, while others you may not recognize. As a rule of thumb, you should only disable programs you are certain about to prevent unexpected software failure. Placing a check in the box next to the program name causes the program to launch with Windows 7. Removing the check in the box prevents the program from launching.

Click the "Services" tab, then select the "Hide all Microsoft services" option in the bottom left corner. This ensures you don’t disable a service required by Windows. You will now see only the third-party services that launch when Windows 7 starts. Remove the check in the box next to any services you know that you don’t need. Click "OK" to make the changes, then reboot your Windows 7 computer when prompted.
You should see an immediate improvement in startup speed.