Firefox is a browser rather than a search engine.

I can not immediately think of any great features stripped out of Firefox8 that were present in Firefox 7. Possibly the problem is with some of the software extensions you use, maybe you can say what is not working.

If you wish to downgrade then Firefox 3.6 is still supported and secure:

• see installing a previous version of firefox
  (That may be a rather drastic step, and may result in loss of some features, or compatibility problem)

My bank in Canada says it has a new feature -a security wrap (I can't remember the exact term they used) for its website that will work with anti-virus ware. It says it will identify fake sites and also insulate the site and input even if the computer is infected. HOWEVER, it does NOT support this new Version 8 of Firefox. This is not surprising since V8 slows to a crawl after a few hours and is generally a whole lot more difficult.

I am going to have to use IE and/or downgrade to 3.6. 

Look Mozilla, "streamlining" menus is another term for making it as difficult as possible for users to find a needed function. Dec 2011

To reiterate, Firefox is a browser rather than a search engine. It looks as though you are not happy with the browser. Perhaps your problem could be solved if you list exactly what about the new browser causes you difficulty, that is, in exactly what context it occurs.