MS office 2000

I am running both XP SP2 and Vista on different drives in the same PC, I would like to access Outlook from both OS’s. Is this possible. Vista tells me to run setup for office when I try to any office programs from the XP location, even in XP compatability mode. I’m afraid I’ll end up with email scattered in two places and need to change OS’s just read tham, or always backup and restore the .pst files. I know word and excel are simple to do by telling the software were to save the file in the options.