I suggest you look at using the Robocopy utility that comes with with the Windows 2000 Server Resource Kit. (there's apparently an XP and .Net version linked from that same page). It does robust filecopy, can sync directories, preserve security settings, can use UNC notation instead of mapped drives, can do retries, etc.

Use your GUI to get the right parameters for Robocopy, then parse Robocopy's output to summarize for the user what was done, etc. Robocopy could even make records in an administrative log for your monitoring needs.