How can I determine in the login script what OS the user is running so the correct front end database program is pushed to their desktop?

Here's what we are using right now:

IF INGROUP ("BFA2000W2K") = 1
$file1="i:\bfsprog 2000.mdb"
$file2=ReadValue("HKEY_CURRENT_USER\Software\Microsoft\Windows\CurrentVersion\Explorer\Shell Folders","Desktop")
$file3=$file2+"\bfsprog 2000.mdb"
$file4=$file2+"\bfsprog.mdb"
$Result1 = GetFileTime($file1)
$Result2 = GetFileTime($file3)
$Result3 = Exist($file4)
;Deletes the OLD BFAPRODG file from the desktop
If $Result3 = 1
$t = "Deleting your old BFA Database File - Please wait..." GOSUB text
DEL $file4
Endif
;? "Desktop Database File: "+$result1+" Server Database File: "+$result2 ;Shows the file times on the login script
IF ($Result2 <> $Result1) ;Does File2 = File1?
$t = "Updating your BFA Database File - Please wait..." GOSUB text
COPY $file1 $file2
Else
$t = "You have the most recent BFA Database File..." GOSUB text
ENDIF
ENDIF

Thanks in advanced for your help.

Tom Few
Pittsburgh, PA