One suggestion is to write a batch (.bat) file that will call your executable. The batch file can contain all the standard inputs necessary to run the executable. Then, in LabVIEW, you can call the .bat file using the System Exec.vi.
As far as your second question, there is no slick way to do this LabVIEW. You would probably have to call Window API functions using the Call Library Function utility. There is a set of VI's that call some of the standard API functions but I don't think they have what you want.
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