Get a Field Object, not FieldInfo, from a VB Class Instance

I am trying to iterate through objects (fields) in a class and invoke a method on each object. Each object is of a different type. Here is the parent class:

Public Class MySettings
    Public IdentifyByFacType As RadioButtonSetting

    Public WtrFacTypes As ListSetting
    Public OilFacTypes As ListSetting

    Public GroupByRef As CheckboxSetting
    Public GroupRefAttr As TxtboxSetting
End Class

Here is part of one of the sub-object classes:

<Serializable>
Public Class TxtboxSetting
    <XmlIgnore()>
    Public MyControl As Windows.Forms.TextBox
    <XmlIgnore()>
    Public DefaultSetting As String

    Private _SavedSetting As String

    Public Property SavedSetting As String
        Get
            Return _SavedSetting
        End Get
        Set(value As String)
            _SavedSetting = value
            CurrentValue = value
        End Set
    End Property

    Public Sub New()
    End Sub

    Public Sub New(DefaultSetting As String, MyControl As Windows.Forms.TextBox)
        Me.DefaultSetting = DefaultSetting
        Me.MyControl = MyControl
    End Sub

    Public Sub RestoreDefault()
        CurrentValue = DefaultSetting
    End Sub
End Class

All of the sub-objects of the MySettings class, like GroupRefAttr for example, have the same methods and properties, but the internal code is different.

So I will have several classes like the MySettings class, and each one will have different sub-objects. Given an instance of such a class, I want to automatically iterate through the fields and call a method RestoreDefault on each one. I don't want to have to know what objects exist in the MySettings class. Rather, knowing that they all have the RestoreDefaultmethod, I want simply call the method on each object.

Despite much searching, I have not found a way to do this. With reflection, I can only get this far:

Dim Opts as New MySettings
For Each var In Opts.GetType.GetFields
    Dim RestoreDefault As System.Reflection.MethodInfo = var.FieldType.GetMethod("RestoreDefault")
    RestoreDefault.Invoke(Opts, Nothing)
Next

However, in the line RestoreDefault.Invoke(Opts, Nothing), I can't just pass in Opts, as I am dealing with a field in Opts, not Opts itself. A statement like this would work: RestoreDefault.Invoke(Opts.GroupRefAttr, Nothing), but that requires me to know the objects in the MySettings class ahead of time, and that defeats the purpose. Is there a way to grab field instance objects at runtime and pull this off?