Over time, my computer getting slower on starting up. Happen to find this command MSConfig to the rescue.
How to perform a clean boot in Windows XP: "How to perform a clean boot in Windows XP
Note You must be logged on as an administrator or a member of the Administrators group to follow these steps. If your computer is connected to a network, network policy settings may also prevent you from follow these steps. 1.Click Start, click Run, type msconfig in the Open box, and then click OK.
2.On the General tab, click Selective Startup, and then clear the Process System.ini File, Process WIn.ini File, and Load Startup Items check boxes. You cannot clear the Use Original Boot.ini check box.
3.On the Services tab, select the Hide All Microsoft Services check box, and then click Disable All.
4.Click OK, and then click Restart to restart your computer.
5.After Windows starts, determine whether the symptoms still occur.
Note Look closely at the General tab to make sure that the check boxes that you cleared are still cleared. Continue to step 6 if none of the check boxes are selected. If the Load System Services check box is the only disabled check box, your computer is not clean-booted. If additional check boxes are disabled and the issue is not resolved, you may require help from the manufacturer of the program that places a check mark back in Msconfig.
If none of the check boxes are selected, and the issue is not resolved, you may have to repeat steps 1 through 5, but you may also have to clear the Load System Services check box on the General tab. This temporarily disables Microsoft services (such as, Networking, Plug and Play, Event Logging, and Error Reporting) and permanently deletes all restore points for the System Restore utility. Do not do this if you want to retain your restore points for System Restore or if you must use a Microsoft service to test the issue.
6.Click Start, click Run, type msconfig in the Open box"