change permissions to copy pictures into backgrounds

[Thomas Blasejewicz]

Good evening
The other day I newly installed Ubuntu 12.04.
I tried to copy pictures into the default folder. I was denied access
(allowed to copy those files), because
I have not the right permissions.
Looking at the properties shows, that the "owner"is root.

I tried to find answers online, where I got "sudo naut ... " or
"sudo chmod ..." etc. but none of those tricks has worked yet.

I would love to have the option (apparently not available) to CHOOSE the
default folder for my wallpapers.
If that is not possible, I would like at least to be able to copy a
little something into the default folder.

What is the try, that will allow me to do so?

Thank you.