i can help you with #1
Set a reference to the Windows Common Dialog Control by right clicking in the controls toolbox and selecting Components and then the Windows Common Dialog Control. Draw one on your form and then put this in your button click routine.
Code:
Private Sub cmdOpen_Click()
CommonDialog1.ShowOpen
'then in here put all of the properties and stuff that you want, like if you want to have the dialog box open up to a specific directory automatically
CommonDialog1.InitDir = "'put the directory here"
'or if you want to save the name of the selected file to a variable
strFileName = CommonDialog1.FileName
End Sub
as for the other 2 questions, sorry I have not a clue 
cheers
Andrew