Their is a program called MozBackup that will back up your FF and Thunderbird profiles , including the bookmarks and e-mails. Quite useful to this once in a while in just to be on the safe side - I also got hit with a virus and lost bookmarks , emails etc
You can also manually save your bookmarks , Organize bookmarks , File , export. I doubt that this method will save your passwords and logins , but using MozBackup will.