Yes exactly, you can always reset to the actual templates. This is why I made copies from the stylesheets/templates that I changed to my likings and keep that in a folder on my pc, so I can always go back to that and not to the actual Montezuma colors and stuff. It would take me ages to change it all back to what I want, so this is a good option.
About the Footer: I did what you adviced CrouchingBruin, and made a widget with that tip you gave me from the other question I asked (about social media). I added <?php dynamic_sidebar( 'Widget Area FOOTER' ); ?>
into the footer.php and yay, that works! I am excited, it's magic haha. And then I added a text widget to it and put some lines in it et voila, it appeared exactly how I want it to be. So that's awesome. Thanks a bunch (also to gk)!
You can see it here: http://creacont.nl/