There are many reasons why it's sometimes useful to disable programs at startup in Windows XP. For example if your computer is freezing up or you want to identify potential issues with system performance, then it's sometimes helpful to turn off programs at startup as a part of the troubleshooting process. Other reasons for turning off programs could be to free up memory to increase system performance, or to simply eliminate potential conflicts that might arise. There are other reasons not listed here.
1. Click on Start.
2. From the Start Menu Options choose Run.
3. Type “msconfig” without quotes and click okay. This will bring up System Configuration Utility.
4. System Configuration Utility >> Click the tab called Startup.
6. Now you can uncheck any programs that you do not want running upon startup.
7. Once you are done unchecking Click Okay and you will be prompted to restart your computer.
The image shows the System Configuration Utility in Windows XP.