how to save an Excel file with Visual basic .NET

Right know Im using this code to open an existing excel file to modiy it, and save it with other name

        Dim oSheet As Object
        Dim xlTemp As Application

        xlTemp = New Application
        xlTemp.Workbooks.Open("C:\plantilla1.xls")
        oSheet = xlTemp.Worksheets(1)
        oSheet.Range("A1").Value = "Last Name"
        oSheet.Range("B1").Value = "First Name"
        oSheet.Range("A1:B1").Font.Bold = True
        oSheet.Range("A2").Value = "Doe"
        oSheet.Range("B2").Value = "John"
        xlTemp.SaveWorkspace("c:\test.xls")
        xlTemp.Quit()

This works ok, but I would like to know how to save the file with other name using a classic "save as file dialog" windows with VB

is that possible???

An also I have another problem with my code as you can see the excel remains on the process list
I woul like to know how to remove the excel process after I close the application by code