As Windows starts up there are many programs that are executed automatically, some of which you may not want starting up, and many of which do not need to be started every time your computer is booted up. If you look at your toolbar, normally in the area directly adjacent to where your clock is displayed, you will probably see many small icons that correspond to various applications that are installed on your system. Each of those icons actually represents an application that is running in the background of your system, using up valuable system resources.
The majority of applications that add themselves to the start-up sequence do not absolutely need to do so. Removing some of these applications from your startup sequence can greatly increase system performance. Do not be alarmed if you remove an application from the start-up sequence and you no longer see its icon in your task-bar area. You can still access any application removed from the start-up sequence simply by either clicking on its shortcut on the desktop (assuming there is one) or by clicking start and browsing through the programs listing until you find the application and then starting it from there.
As a general rule the only programs that absolutely have to be running in the background are the ones that are associated with your network hardware. Typically if you are using a wireless network adapter then you would most likely need to be sure that you do not remove that application from the start-up sequence. There could also be other applications that might support some proxy services or VPN services that might also need to be running depending on your specific situation. Every situation is different, you may need to experiment a bit to find the best configuration.
Luckily, in their infinite wisdom, Microsoft included a utility starting with Windows 98 that allows you to modify the start-up sequence relatively easily.
Using 'MSCONFIG'
Windows XP
Click on Start->Run
Type 'msconfig' and press enter or click OK. (The System Configuration Utility should start up.)
Windows Vista / Windows 7
Click on Start
In the search system box type 'msconfig' and press 'Search'.
In the System Configuration Utility, click on the tab called Startup.
You can uncheck any program that you do not wish to execute on startup. (Changes that you make here are easily reversible.)
After you have unchecked as many or few programs as you wish, click 'Apply' and then 'OK'.
You will then be prompted to restart your computer, click 'Yes'.
If after rebooting you are experiencing problems connecting to the Internet or you are not able to access certain software you can easily go back and recheck those programs in the 'msconfig' utility using the same steps outlined above.
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