It's difficult to answer this accurately, but Drag and Drop is not difficult.
Assuming you want to drag an image from Explorer onto you form:
1) Set the Form AllowDrop property to true.
2) Handle the Form DragEnter event.
If e.Data.GetDataPresent(DataFormats.FileDrop) Then
e.Effect = DragDropEffects.Copy
e.Effect = DragDropEffects.None
3) Handle the Form DragDrop event.
Dim files As String() = DirectCast(e.Data.GetData(DataFormats.FileDrop, False), String())
For Each file As String In files
You can then check for images and use the file as you wish.