I know it changed quite a bit-

try going to View in FF menu bar & then Customize -
in that apt you can drag the Home button & any other button to where you want it.

Also if you want bookmarks to have a special place showing click the bookmarks option in that same drop down menu area.
I un-clicked the Tabs on Top also- I didn't like the look that way.

If you try something and don't like it just change it back or the customize area has a Default - button will put it all back to original.

Did you look at those links for how to make 7 look more like XP ?
on the other thread?

I don't care for Vista's looks either - when I go to work on my aunts laptop LOL I wish I could change it....