any suggestions ...yes you sound like you are the only user of this lappie?
1) use your filemanager to show hidden files.
delete /home/name/.mozilla.......then retest your existing firefox
2) If that fails to speed up good news.....firefox is now 3.5.5
download the latest....do not attempt to open current one and run update check.
put the tarball under your /home/name
Use your package manager to delete existing firefox
open a terminal and run this command to unpack new one
tar jxvf firefox-3.5.5.tar.bz2
this means you have a folder called /home/yourname/firefox
2) create a shortcut on desktop to /home/name/firefox/firefox
I do not know how to do that with your distro sorry
but we can cheat if you do not know how....by creating a symlink
ln -s /home/name/firefox/firefox /home/name/firefox
then running firefox....from a terminal or pressing ALT (and) F2 keys brings up run box and type firefox
the you can see if that fixes your problem