JJ's dashboard

Hello! I resigned from a law firm recently and was not able to remove firefox due to admin settings on the company PC. All of my firefox and XMARKS bookmarks, saved passwords, etc. are on that PC. How can I remove that info - especially the bookmarks - from my home PC and disallow someone else to access that info from that PC? I thought of resetting my xmarks password on my home PC; will that do the trick? I really want to make sure my bookmarks aren't being viewed on another PC. Please advise. Thank you!