Open up your terminal program (Konsole / GNOME Terminal). At the prompt, type:
su -
<enter root password>
In that terminal, you are now root: you have access to everything. If you want to view permissions, use the "ls -l" command on a file. To change ownership, use "chown", and to change permissions, use "chmod". These commands all have man pages that you can view to figure out how they work.

If you need to access /boot, this is the way to do it. But almost all work should be done as your regular user.