Permissions
 

Im obviosuly very new to Linux, and I'm somewhat confused by its permissions structure.

I am trying to simply install Mozilla, but apparently, I can't install it anywhere except my home folder. I read something about the root user being able to do things and I thought I put myself in the root group (but im not so sure anymore seeing how this isn't working. Whenever I try to pick a directory It gives me an error saying the directory can't be created.

http://www.newtolinux.org.uk/tutoria...missions.shtml
there is difference between root(owner) and group(what you are using)
a file would be like this
rwxr--r-- (ie 744 would be readable and and writable only by root, and not the group,which has only read permission).
If you want to make mozilla available to other users you could also try suid
(see manpage of chmod
man chmod
and
man chgrp
and
man chown
)