This is more of a windows question than a perl question. But what you are looking for is probably in the registry. A quick check brought me to this key:

HKEY_CURRENT_USER\Software\Microsoft\Windows\CurrentVersion\Explorer\A
+dvanced
[download]

If this is the case, then you can use Win32::TieRegistry which comes with ActivePerl. You might want to do a search at mdsn.

Update: I found that key on a Win2k Server, I don't know if it's different on NT\9x\Me. Check MDSN

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