This will clear the clipboard
Sub ClearClipBoard()
Application.CutCopyMode = False
End Sub
I think this would suppress the alerts
Application.DisplayAlerts = False
'... code here...
Application.DisplayAlerts = True
Chip Pearson has a page on use of the Clipboard, if
questions are not answered there you should have a better
idea of what to search on for other solutions.
http://www.cpearson.com/excel/clipboar.htm