I am rather baffled as to what has happened to you.

AFAIK Firefox should not upgrade from the previous main version 3.6, to Firefox 4 without warning you, and any upgrades from 4.0 to 4.0.1 should try to retain your passwords and other data.

If however you uninstall Firefox and use the option to clear data, or however it is worded, then Firefox does delete bookmarks and passwords etc, you then need luck and a file recovery utility if you wish to recover bookmarks. Some users with that problem do get lucky eg see /questions/787020#answer-141048 (that thread also contains information about backing up bookmarks)

I am hoping you did not delete your data if so have you looked at this article:

• lost bookmarks

Ok this is bizzare!

Thank you for your response, I went throught each and every step without any luck, even got the recovery programme, and painstakingly tried to sift through all that mumbojumbo to find what i needed. finally found the bookmark bit, but it had been fully overwritten :(, so on reading about previous ff versions, found the sqlite thingys, and they were relatively unscathed(partly written over, but saveable apparently TG), saved them to adiff drive, amongst other possibly good folders. Then looked up how to install them, and it said to close FF, and install to profile folder.

So i tried to close FF, and the original problem from a few days ago, where it asked me if 'i was sure i wanted to close this window as it has X tabs open', popped up again. This is where 'open blank page' selection was set, over 'open previous tabs'. Wanting to save that info on how to sort out these friggin files, I reset the Option to 'open previous tabs', and closed FF. After unsucessfully searching for the profile folder on my laptop, i opened FF intending to search online for where i could find said folder.

AND BANG, surprise surprise, the FF I had just closed with only tabs open about finding out what the heck to do, had disappeared, and instead my original saved tabs were up, and my bookmarks are there..... I am gobsmacked! what the heck just happened there???

I have made 3 back up in different folders now, of those friggin bookmarks. I am weary now tho of shutting it all down.... what if its back to the other pages I had with no bookmarks, tomorrow :(

Just some general comments

Bookmarks & backups firefox does save bookmarks and tries to save copies of these as backups, one problem is that it saves the backups in the profile. You have the option of manually overwriting the current files using the backup. And if there are problems firefox will try to use the files to recreate a good set of bookmarks. As you have noticed the History is saved in the same files.
If however there are problems with the profiles those bookmarks history and backups can be lost or corrupted. It makes sense imo to make sure you keep your own manual backups somewherer safe.

• see Restore bookmarks from backup or move them to another computer

"After unsucessfully searching for the profile folder on my laptop, i opened FF intending to search online for where i could find said folder. "
Easiest method of finding the profile folder is using firefox itself

• Firefox button -> Help -> Troubleshooting Information [Open Containing folder]
• or type into the location bar "about:support" include the colon [:] but not the ["]
• see also profiles

Thank you for your help, I really appreciate it.

Glad to be of assistance.