The file README in mozilla-i686-pc-linux-gnu-1.7.7-installer.tar.gz/mozilla-installer

lines 79-94: "To install Mozilla by downloading the Mozilla installer, follow 
these steps:

1. Create a directory named mozilla (mkdir mozilla) and change to that 
directory (cd mozilla).
	
2. Click the link on the site you're downloading Mozilla from to download the 
installer file (called mozilla-i686-pc-linux-gnu-installer.tar.gz) to your 
machine.

3. Change to the mozilla directory (cd mozilla) and decompress the archive 
with the following command:

  tar zxvf moz*.tar.gz

The installer is now located in a subdirectory of Mozilla named 
mozilla-installer.

4. Change to the mozilla-installer directory (cd mozilla-installer) and run 
the installer with the ./mozilla-installer command.

5. Follow the instructions in the install wizard for installing Mozilla."

   The wizard only installs Mozilla in an empty directory, or on a previous 
installation, NOT in a directory that contains a subdirectory named 
mozilla-installer. I would rewrite it as follows:

"To install Mozilla by downloading the Mozilla installer, follow these steps:

1. Download the installer file (called 
mozilla-i686-pc-linux-gnu-*-installer.tar.gz) and extract it at a known 
place. The extraction will create a subdirectory called mozilla-installer

2. Enter mozilla-installer/ (cd mozilla-installer) and run the installer with 
the ./mozilla-installer command.

3. Follow the instructions in the install wizard for installing Mozilla."

   My opinion may be stupid as I'm brazilian and I badly know english.