Why get rid of Vista- it's fine. You should have either got an Office disc with word on it, or the computer should have a free 90 day trial of word 2007 included. Although a little unfamiliar initally, I think Word 2007 is far better than 2003. If you have the xp disc for windows then you can uninstall visat and reinstall xp.
memoo - not sure of your tech level, but Vista is an operating systen & Word is a program, they are independent of each other -Word 2003 will work on Vista as well as XP and Word 2007 will work on XP as well as Vista.
Is it just the version of Word you've got that you don't like about your new PC, because if so you can put Word 2003 on - though you will have to buy it if you don't already have it.
I didn't like Word 2007 at first, but it's growing on me - it's a good idea to spend some time ust clicking on all the icons just to see what they've put where.
The biggest problem is the incompatibilty between different types of graphics - which means for example you can't put Word Art on top of some pictures, but there are ways round even that.