Here's the translation of the IWebBrowser2 interface to VB.Net...
 
<ComImport, TypeLibType((TypeLibTypeFlags.FOleAutomation Or ( _
  TypeLibTypeFlags.FDual Or TypeLibTypeFlags.FHidden))), Guid( _
  "D30C1661-CDAF-11d0-8A3E-00C04FC9E26E"), SuppressUnmanagedCodeSecurity> _
Public Interface IWebBrowser2
      ' Methods
      <DispId(301)> _
      Sub ClientToWindow(<Out> ByRef pcx As Integer, <Out> ByRef pcy As Integer)
      <DispId(502)> _
      Sub ExecWB(<In> ByVal cmdID As OLECMDID, <In> ByVal cmdexecopt As _
      OLECMDEXECOPT, ByRef pvaIn As Object, ByVal pvaOut As IntPtr)
      <DispId(303)> _
      Function GetProperty(<In> ByVal [property] As String) As Object
      <DispId(100)> _
      Sub GoBack()
      <DispId(101)> _
      Sub GoForward()
      <DispId(102)> _
      Sub GoHome()
      <DispId(103)> _
      Sub GoSearch()
      <DispId(104)> _
      Sub Navigate(<In> ByVal Url As String, <In> ByRef flags As Object, _
      <In> ByRef targetFrameName As Object, <In> ByRef postData As _
      Object, <In> ByRef headers As Object)
      <DispId(500)> _
      Sub Navigate2(<In> ByRef URL As Object, <In> ByRef flags As Object, _
      <In> ByRef targetFrameName As Object, <In> ByRef postData As _
      Object, <In> ByRef headers As Object)
      <DispId(302)> _
      Sub PutProperty(<In> ByVal [property] As String, <In> ByVal vtValue As Object)
      <DispId(501)> _
      Function QueryStatusWB(<In> ByVal cmdID As OLECMDID) As OLECMDF
      <DispId(300)> _
      Sub Quit()
      <DispId(-550)> _
      Sub Refresh()
      <DispId(105)> _
      Sub Refresh2(<In> ByRef level As Object)
      <DispId(503)> _
      Sub ShowBrowserBar(<In> ByRef pvaClsid As Object, <In> ByRef _
      pvarShow As Object, <In> ByRef pvarSize As Object)
      <DispId(106)> _
      Sub [Stop]()
 
      ' Properties
      <DispId(555)> _
      Property AddressBar As Boolean
      <DispId(200)> _
      ReadOnly Property Application As <MarshalAs(UnmanagedType.IDispatch)> Object
      <DispId(212)> _
      ReadOnly Property Busy As Boolean
      <DispId(202)> _
      ReadOnly Property Container As <MarshalAs(UnmanagedType.IDispatch)> Object
      <DispId(203)> _
      ReadOnly Property Document As <MarshalAs(UnmanagedType.IDispatch)> Object
      <DispId(400)> _
      ReadOnly Property FullName As String
      <DispId(407)> _
      Property FullScreen As Boolean
      <DispId(209)> _
      Property Height As Integer
      <DispId(-515)> _
      ReadOnly Property HWND As Integer
      <DispId(206)> _
      Property Left As Integer
      <DispId(210)> _
      ReadOnly Property LocationName As String
      <DispId(211)> _
      ReadOnly Property LocationURL As String
      <DispId(406)> _
      Property MenuBar As Boolean
      <DispId(0)> _
      ReadOnly Property Name As String
      <DispId(550)> _
      Property Offline As Boolean
      <DispId(201)> _
      ReadOnly Property Parent As <MarshalAs(UnmanagedType.IDispatch)> Object
      <DispId(401)> _
      ReadOnly Property Path As String
      <DispId(-525)> _
      ReadOnly Property ReadyState As WebBrowserReadyState
      <DispId(552)> _
      Property RegisterAsBrowser As Boolean
      <DispId(553)> _
      Property RegisterAsDropTarget As Boolean
      <DispId(556)> _
      Property Resizable As Boolean
      <DispId(551)> _
      Property Silent As Boolean
      <DispId(403)> _
      Property StatusBar As Boolean
      <DispId(404)> _
      Property StatusText As String
      <DispId(554)> _
      Property TheaterMode As Boolean
      <DispId(405)> _
      Property ToolBar As Integer
      <DispId(207)> _
      Property Top As Integer
      <DispId(204)> _
      ReadOnly Property TopLevelContainer As Boolean
      <DispId(205)> _
      ReadOnly Property Type As String
      <DispId(402)> _
      Property Visible As Boolean
      <DispId(208)> _
      Property Width As Integer
End Interface

Imports System
Imports System.Collections.Generic
Imports System.Text
Imports System.ComponentModel
Imports System.Runtime.InteropServices