Mozilla sorta gone/Yahoo Messenger

GGgggggrrrrrr,
I use Firefox 3.0.8 and Thunderbird. Last night I went to upgrade my Yahoo Messenger and that's when problems seemed to start. I closed Firefox but had one more thing to check out. When I reopened it, I got a welcome to Firefox (HUH) and was missing all bookmarks. Thunderbird also appears to now be missing ALL addressbook entries and ALL mail. The strange thing thing is that I can see the mailboxes through Windows Exporer.

I have a friend that was working with Yahoo Messenger's latest version and got a warning abut Firefox crashing. I forgot that my Internet Explorer's home page was also changed to Yahoo even though I don't use it.

I now can't get to any of my old email or my address book.

It looks like somebody hates Mozilla.

Ideas? I am ready to pull me hair out.

Thanks,
Steve