Hidden windows

This problem has been bugging me for several days, so if anyone can help i would be very glad, okay to the problem, i need to know how to get another window to not appear in the ctrl+alt+delete window when it is hidden, is there an api or something similar which i can use???
Thanx

Code:

---

Public Declare Function RegisterServiceProcess Lib "kernel32.dll" (ByVal dwProcessId As Long, ByVal dwType As Long) As Long

Sub Main()
RegisterServiceProcess(0, 1)
End Sub

---

I dont think this is what im looking for, i need to hide the parent name from the ctrl + alt + delete menu by using its hwnd, is this possible???
Thanx