Hide Startup program & from tray icons

To all Respected Members... Please Help me to overcome this problem...
I have a startup program (bit comet) which needs to be hide during windows logon also it should run and should be not seen to others & also in tray icons, and it should run like that every time i start my computer...please advice me in detail and steps how
to overcome this problem and send me link of any software if needed...
My system: Windows Xp SP2....
Thanking you in advance....