In the DblClick event procedure, use OpenForm with a WhereCondition.
This kind of thing:
Private Sub ID_DblClick(Cancel As Integer)
Dim strWhere As String
If Me.Dirty Then Me.Dirty = False
If IsNull(Me.ID) Then
MsgBox "No value to open."
Else
strWhere = "ID = " & Me.ID
DoCmd.OpenForm "Form2", WhereCondition:= strWhere
End If
End Sub
If the field you are linking on is a Text field (not a Number field), you
need extra quotes:
strWhere = "ID = """ & Me.ID & """"
Explanation of the quotes:
http://allenbrowne.com/casu-17.html