FYI this seems like a very bad idea. You could render your system useless if you kill the wrong process. The codes I posted above also depends on how your ps renders the data (linux, fbsd, unix, etc) so be sure to test.
I'm sure Salem will be along with a more graceful solution :)
For Each ctrl As Control In Me.Controls("pnlMainPanel").Controls
If ctrl.GetType Is GetType(System.Windows.Forms.Panel) Then
For Each subCtrl As Control In ctrl.Controls
If subCtrl.GetType Is GetType(System.Windows.Forms.TextBox) Then
If subCtrl.GetType Is ...