Some or most of the icons dissapear on the task bar .  When I check the speakers  and network connections the box is checked to desplay these.  Other Icons also dissapear.  This is on XP home eddition.  There is only the quick launch tool bar using the area and there is plenty of room.

Look at Control Panel\Task Bar and Start Menu. Under the notification area heading, there is a check box that says hide inactive icons. If you want all the icons to show all the time, uncheck this.
Otherwise, click the customize button and you can set each individual icon to always show, hide when inactive or always hide.

The show/hide checkbox is already unchecked.  

What configuration do you see when you click the customize button? Some one may have set the missing icons to not show.

   The SysTray value must be in the HKEY_LOCAL_MACHINE\SOFTWARE\Microsoft\Windows\CurrentVersion\ShellServiceObjectDelayLoad key of the registry.  If it is not there, try adding a string value to ShellServiceObjectDelayLoad (right click on it and select New then String Value) with a value name of SysTray and value data of {35CEC8A3-2BE6-11D2-8773-92E220524153}