Originally Posted by linuxpng2
..and i want the script (or however it can be done) to be executed from XP..
Well, if you really want to have the thing run under Windows, there's a pretty easy to use Windows program named "SyncBack". http://www.2brightsparks.com/
If you dig around on the website you'll find a free version amongst the various "for sale" versions. They try to hide it a bit, but it's there if you search.
Rather than the above, I would recommend that you tell your users to create a special directory, copy everything they want backed up to it, and share it with an obvious sharename like "BACK_ME_UP". Then from your Linux box, crawl your network looking for things to backup. That way you increase reliability (you're using Linux for the work, not Windows), and you're also cutting down on support costs (you don't have to go to all those Windows PC's and fix your user's misconfigurations of SyncBack).