The run time version of Access 2007 can only run on XP SP2 or better. So your choices are limited on 2000. You can run a virtual machine with XP SP2 and work in there or upgrade your system. You can not downgrade your database.
The run time version of 2007 can be found here: http://www.microsoft.com/downloads/details.aspx?familyid=d9ae78d9-9dc6-4b38-9fa6-2c745a175aed&displaylang=en