Have a look through this linky. http://kb.mozillazine.org/Reducing_memory_usage_(Firefox)
P.S. Keep NoScript as the more I learn about exploits the more they depend on javascript, Flash, etc. If that method doesn't work then they try to throw a PDF or download your way.
Edit: Here is how to backup and restore your bookmarks.
http://kb.mozillazine.org/Backing_up...arks_-_Firefox