You can do with it whatever you want. It depends on what you mean with disabling. If you want to capture all keyboard/mouse input, you'll could make a system wide hook. But an easier approach would be just to hide the Taskbar, which can be done like this:
[tt]
Option Explicit
Private Declare Function FindWindow Lib "user32" Alias "FindWindowA" (ByVal lpClassName As String, ByVal lpWindowName As String) As Long
Private Declare Function ShowWindow Lib "user32" (ByVal hWnd As Long, ByVal nCmdShow As Long) As Long
Private Const SW_HIDE = 0
Private Const SW_NORMAL = 1
Private Sub Command1_Click()
Dim hWnd As Long
hWnd = FindWindow("Shell_TrayWnd", ""

Call ShowWindow(hWnd, SW_HIDE)
End Sub
Private Sub Command2_Click()
Dim hWnd As Long
hWnd = FindWindow("Shell_TrayWnd", ""

Call ShowWindow(hWnd, SW_NORMAL)
End Sub
Private Sub Form_Load()
Command1.Caption = "Hide"
Command2.Caption = "Show"
End Sub
[/tt]