With WindowsXP, you can manually select how you want individual icons in the System Tray to be displayed.
- Right click on the Taskbar
- Select Properties
- Check Hide inactive icons
- Click on the Customize button
- This will bring up a dialog box that will allow you to select one of three options for your applications: Hide when inactive, Always hide, or always show
- Highlight current or past applications and make any changes you like
- A small arrow will now appear in the System Tray that will allow you to show or hide these icons