I think if the chmod doesn't work, you'll need to sudo it.
sudo - super user do, it also requires the administrator's password.
It's easy to mess stuff up with sudo, so use it with caution.
I recommend doing this:
Make sure you're in the trash folder. If the files in your trash are directories and those directories have subdirectories, you might need to change permissions on all of them. Easiest way to do this is:
chmod -R 777 *
What this does is changes the permissions of everything to 777, and will recursively do so for every item (even in subdirectories).
Once that's done do:
rm -rf foldername
In this case, do not use *, this is because it will delete everything in the trash, and sometimes it can mess things up. The r is for recursive and f is for force. These are explained below.
Whenever I'm working on a friend's Mac, and they have stubborn folders/files that need to be deleted, I do this:
Make sure they are on the desktop, if I cannot click and drag, I use terminal for everything.
cd <to where the file/folder is located>
(optional) chmod -R 777 <file/folder name>
sudo rm -rfv <file/folder name>
So I locate the file, change the permissions and then to make sure I delete it, I sudo rm (remove) -rf (recursively and force) the file/folder. the force is used in addition to sudo to pretty much tell the Mac that I mean serious business. I use v (verbose) to allow me to see what files are being deleted. I'm a bit of a log nerd, so I like to see what it does.
I'm sorry if I'm stepping on TEG's parade, or ranting to something that was completed; I just like it when people explain how they do things.
