How to open DTS packages which are written in SQL Server 2000 or 2005 in SQL Server Management Studio 2008?
download application from following link
download “Microsoft SQL Server 2005 Backward Compatibility Components”
SQLServer2005_BC*.exe or msi according to your machine requirement.
then open SQL Management studio 2008 and double click on DTS. you would be able to open on SSMS 2008.