Installation of phpMyAdmin

Hello everyone.
So, i am trying to install phpMyAdmin, as someone on an earllier thread suggested i do so, so to enable deletion of guestbook entries. excellent.

i have downloaded the phpMyAdmin-2.6.3-pl1.tar.gz in my machine.
when i follow the instructions

unzip the distribution (be sure to unzip the subdirectories): tar -xzvf phpMyAdmin_x.x.x.tar.gz in your webserver’s document root. If you don’t have direct access to your document root, put the files in a directory on your local machine, and, after step 3, transfer the directory on your web server using, for example, ftp.

now i have the problem : do i try to unzip them on my machine and if so how ?
i tried to already but i just get pointed to services / packages on the web.

alternatively, i uploaded the gz file straight to my web server, and attempted to edit it from there, and all i get is the message :
Oops - an error has occurred:
phpMyAdmin-2.6.3-pl1.tar.gz is larger than 100k and cannot be edited by the CNC.

so this is where i am right now, any hints as to where i might move on ?

thanks for any advice, and have a great day !