Most of the programs will have an option that lets you select if you want the program listed in start-up list or not. Another way of directly removing the program from the list from windows xp is :
1> Go to ‘Start’ menu – ‘Run’
2> Type ‘Msconfig’ and press enter.
3> A window with a lot of tabs pops up. Choose ‘Startup’ tab.
4> In the startup tab you’ll see a set of programs that’ll run as soon as the system starts. Uncheck those programs which you wish not to be there in the list. Click on ‘OK’. Next time when you start the system, those programs won’t start during Windows Start up.
You can also try ccleaner as it lets you delete unwanted startup items easily.