I run Office 2003 Pro and Office 2007 Home And Student on an XP machine fine. When you install 2007 make sure you change the default directory to C:\Program Files\Microsoft Office 2007 or it will overwrite your existing 2003 install. Once installed both will run fine-the only problem I've noticed is if you load word 2007 then load 2003 the windows installer box comes up for 2003 for about 2 mins before it starts, but they both run fine, standalone or both at same time. You won't need to make a partition for it, just change the default install folder as above. 2007 takes a little getting used to, but once you have got used to it, it's great. Also don't forget click here for your 2003 installation.