Instalando o Firefox...

Baixe o pacote:

$ wget http://mozilla.hongo.wide.ad.jp/pub/mozilla.org/\
firefox/releases/2.0.0.3/linux-i686/pt-BR/\
firefox-2.0.0.3.tar.gz

Descompactando:

$ tar -zxvf firefox-2.0.0.3.tar.gz

Mova o pacote do firefox para /usr/local/lib/:

# mv firefox /usr/local/lib/

Crie um link em /usr/local/bin/:

# cd /usr/local/bin/
# ln -s /usr/local/lib/firefox/firefox firefox

Execute o comando "firefox" no terminal e teste:

$ firefox

Meu Firefox sempre apresentava um problema mesmo na versão 2.0, ele sempre fechava algumas páginas sozinho perdendo alguma coisa que estava fazendo, isso me deixava nervoso, imagino que você também, por isso resolvi esse problema..

Testando esse comando:

$ ldd /usr/lib/firefox/firefox-bin
/usr/lib/firefox/firefox-bin: /usr/lib/libnss3.so: version `NSS_3.11.1' not found (required by /usr/lib/firefox/firefox-bin)
/usr/lib/firefox/firefox-bin: /usr/lib/libnss3.so: version `NSS_3.10' not found (required by /usr/lib/firefox/firefox-bin)
        libmozjs.so => not found
        libxpcom.so => not found
        libxpcom_core.so => not found
        libplds4.so => /usr/lib/libplds4.so (0x40025000)
        libplc4.so => /usr/lib/libplc4.so (0x40028000)
        libnspr4.so => /usr/lib/libnspr4.so (0x4002d000)
        libpthread.so.0 => /lib/libpthread.so.0 (0x40061000)
        libdl.so.2 => /lib/libdl.so.2 (0x400b2000)
        libgtk-x11-2.0.so.0 => /usr/lib/libgtk-x11-2.0.so.0 (0x400b6000)
        libgdk-x11-2.0.so.0 => /usr/lib/libgdk-x11-2.0.so.0 (0x4038a000)
        libatk-1.0.so.0 => /usr/lib/libatk-1.0.so.0 (0x40406000)
        libgdk_pixbuf-2.0.so.0 => /usr/lib/libgdk_pixbuf-2.0.so.0 (0x4041f000)
        libpangoxft-1.0.so.0 => /usr/lib/libpangoxft-1.0.so.0 (0x40435000)
        libpangox-1.0.so.0 => /usr/lib/libpangox-1.0.so.0 (0x4043c000)
        libpango-1.0.so.0 => /usr/lib/libpango-1.0.so.0 (0x40447000)
        libgobject-2.0.so.0 => /usr/lib/libgobject-2.0.so.0 (0x4047e000)
        libgmodule-2.0.so.0 => /usr/lib/libgmodule-2.0.so.0 (0x404b1000)
        libglib-2.0.so.0 => /usr/lib/libglib-2.0.so.0 (0x404b5000)
        libX11.so.6 => /usr/X11R6/lib/libX11.so.6 (0x40536000)
        libm.so.6 => /lib/libm.so.6 (0x40600000)
        libsmime3.so => /usr/lib/libsmime3.so (0x40623000)
        libssl3.so => /usr/lib/libssl3.so (0x40646000)
        libnss3.so => /usr/lib/libnss3.so (0x40668000)
        libsoftokn3.so => /usr/lib/libsoftokn3.so (0x406d4000)
        libXrender.so.1 => /usr/X11R6/lib/libXrender.so.1 (0x40743000)
        libfontconfig.so.1 => /usr/X11R6/lib/libfontconfig.so.1 (0x4074b000)
        libfreetype.so.6 => /usr/lib/libfreetype.so.6 (0x40772000)
        libXt.so.6 => /usr/X11R6/lib/libXt.so.6 (0x407dc000)
        libXft.so.2 => /usr/X11R6/lib/libXft.so.2 (0x4082d000)
        libxpcom_compat.so => not found
        libstdc++.so.5 => /usr/lib/libstdc++.so.5 (0x40840000)
        libgcc_s.so.1 => /usr/lib/libgcc_s.so.1 (0x408f8000)
        libc.so.6 => /lib/libc.so.6 (0x40901000)
        /lib/ld-linux.so.2 (0x40000000)
        libpangoft2-1.0.so.0 => /usr/lib/libpangoft2-1.0.so.0 (0x40a1a000)
        libXrandr.so.2 => /usr/X11R6/lib/libXrandr.so.2 (0x40a40000)
        libXi.so.6 => /usr/X11R6/lib/libXi.so.6 (0x40a44000)
        libXinerama.so.1 => /usr/X11R6/lib/libXinerama.so.1 (0x40a4c000)
        libXfixes.so.3 => /usr/X11R6/lib/libXfixes.so.3 (0x40a4f000)
        libXcursor.so.1 => /usr/X11R6/lib/libXcursor.so.1 (0x40a54000)
        libXext.so.6 => /usr/X11R6/lib/libXext.so.6 (0x40a5d000)
        libz.so.1 => /usr/lib/libz.so.1 (0x40a6c000)
        libexpat.so.0 => /usr/lib/libexpat.so.0 (0x40a7e000)
        libSM.so.6 => /usr/X11R6/lib/libSM.so.6 (0x40a9e000)
        libICE.so.6 => /usr/X11R6/lib/libICE.so.6 (0x40aa6000)

Dá pra ver que faltam alguns arquivos que dizem "not found" para funcionar corretamente o Firefox...

E onde estao esses arquivos????

Entre novamente em /usr/local/lib/firefox/ e com o comando "ls *.so" veja os arquivos que faltam no seu lib pra seu funcionamento correto.

Agora copie eles para:

# cp *.so /usr/lib/

E teste aquele comando:

$ ldd /usr/lib/firefox/firefox-bin
        libmozjs.so => /usr/lib/libmozjs.so (0x40024000)
        libxpcom.so => /usr/lib/libxpcom.so (0x400be000)
        libxpcom_core.so => /usr/lib/libxpcom_core.so (0x400c1000)
        libplds4.so => /usr/lib/libplds4.so (0x4016b000)
        libplc4.so => /usr/lib/libplc4.so (0x4016e000)
        libnspr4.so => /usr/lib/libnspr4.so (0x40172000)
        libpthread.so.0 => /lib/libpthread.so.0 (0x4019f000)
        libdl.so.2 => /lib/libdl.so.2 (0x401f1000)
        libgtk-x11-2.0.so.0 => /usr/lib/libgtk-x11-2.0.so.0 (0x401f5000)
        libgdk-x11-2.0.so.0 => /usr/lib/libgdk-x11-2.0.so.0 (0x404c9000)
        libatk-1.0.so.0 => /usr/lib/libatk-1.0.so.0 (0x40545000)
        libgdk_pixbuf-2.0.so.0 => /usr/lib/libgdk_pixbuf-2.0.so.0 (0x4055e000)
        libpangoxft-1.0.so.0 => /usr/lib/libpangoxft-1.0.so.0 (0x40573000)
        libpangox-1.0.so.0 => /usr/lib/libpangox-1.0.so.0 (0x4057b000)
        libpango-1.0.so.0 => /usr/lib/libpango-1.0.so.0 (0x40586000)
        libgobject-2.0.so.0 => /usr/lib/libgobject-2.0.so.0 (0x405bd000)
        libgmodule-2.0.so.0 => /usr/lib/libgmodule-2.0.so.0 (0x405f0000)
        libglib-2.0.so.0 => /usr/lib/libglib-2.0.so.0 (0x405f4000)
        libX11.so.6 => /usr/X11R6/lib/libX11.so.6 (0x40674000)
        libm.so.6 => /lib/libm.so.6 (0x4073f000)
        libsmime3.so => /usr/lib/libsmime3.so (0x40762000)
        libssl3.so => /usr/lib/libssl3.so (0x40783000)
        libnss3.so => /usr/lib/libnss3.so (0x407a9000)
        libsoftokn3.so => /usr/lib/libsoftokn3.so (0x40811000)
        libXrender.so.1 => /usr/X11R6/lib/libXrender.so.1 (0x4085d000)
        libfontconfig.so.1 => /usr/X11R6/lib/libfontconfig.so.1 (0x40866000)
        libfreetype.so.6 => /usr/lib/libfreetype.so.6 (0x4088d000)
        libXt.so.6 => /usr/X11R6/lib/libXt.so.6 (0x408f7000)
        libXft.so.2 => /usr/X11R6/lib/libXft.so.2 (0x40948000)
        libxpcom_compat.so => /usr/lib/libxpcom_compat.so (0x4095a000)
        libstdc++.so.5 => /usr/lib/libstdc++.so.5 (0x40971000)
        libgcc_s.so.1 => /usr/lib/libgcc_s.so.1 (0x40a2a000)
        libc.so.6 => /lib/libc.so.6 (0x40a33000)
        /lib/ld-linux.so.2 (0x40000000)
        libpangoft2-1.0.so.0 => /usr/lib/libpangoft2-1.0.so.0 (0x40b4c000)
        libXrandr.so.2 => /usr/X11R6/lib/libXrandr.so.2 (0x40b72000)
        libXi.so.6 => /usr/X11R6/lib/libXi.so.6 (0x40b75000)
        libXinerama.so.1 => /usr/X11R6/lib/libXinerama.so.1 (0x40b7e000)
        libXfixes.so.3 => /usr/X11R6/lib/libXfixes.so.3 (0x40b81000)
        libXcursor.so.1 => /usr/X11R6/lib/libXcursor.so.1 (0x40b86000)
        libXext.so.6 => /usr/X11R6/lib/libXext.so.6 (0x40b8f000)
        libz.so.1 => /usr/lib/libz.so.1 (0x40b9e000)
        libexpat.so.0 => /usr/lib/libexpat.so.0 (0x40bb0000)
        libSM.so.6 => /usr/X11R6/lib/libSM.so.6 (0x40bd0000)
        libICE.so.6 => /usr/X11R6/lib/libICE.so.6 (0x40bd8000)

Pronto, agora seu Firefox está sem falhas e funcionando perfeitamente.

Vlw... fiquem com Deus. =D