Here is the examples I am using. It first checks the group information, then the default printer. If it does not have the correct default printer, it installs the appropriate one, and a secondary printer based on the group the PC is in. If it has the correct default printer it exits, without connecting \ installing the printer again.
Code:
If fnADComputerInGroup('GROUPNAME')=1
If $DefaultPrinter = "\\SERVER\HP LaserJet 4000 Series PCL 6 #2 on SERVER"
RETURN
ELSE
AddPrinterConnection("\\SERVER\hp4000-2")
AddPrinterConnection("\\SERVER\copier1")
? "Added printer connection...."
If SetDefaultPrinter("\\SERVER\HP LaserJet 4000 Series PCL 6 #2 on SERVER") = 0
? "Default printer was set to \\SERVER\hp4000-2, by the Kitchen Area in BLDG 1"
RETURN
EndIf
EndIf
EndIf
UDF CODE, SEALEOPARD CREATED THIS. THEN POSTED NEWER CODE, BUT THIS WORKED FOR ME SO I KEPT IT. 
Code:
fnADComputerInGroup("TestGroup")
Function fnADComputerInGroup($sGroupDN)
Dim $objSys,$objCom,$aMemberOf,$sMemberOf
$objSys = CreateObject("ADSystemInfo")
$objCom = GetObject("LDAP://"+$objSys.ComputerName)
$aMemberOf = $objCom.GetEx("memberOf")
For Each $sMemberOf in $aMemberOf
If InStr($sMemberOf,"CN="+$sGroupDN+",")
$fnADComputerInGroup = NOT 0
Exit
EndIf
Next
$fnADComputerInGroup = NOT 1
EndFunction
