Nothing in your .vimrc file strikes me as a problem except perhaps the line
set clipboard+=unnamed
The issue is that the exclude term of the 'clipboard' option, which is present by default if X is detected, must be the last term. By using +=, you have made unnamed the last term. A better setting would be
set clipboard^=unnamed
which places unnamed first in the option string.
Something else you might try, since an empty .vimrc works for you, is to do a binary prune of your .vimrc file. That is, put a :finish command as the first line in your .vimrc file, restart vim and verify that copying works, then move the :finish command about halfway down your .vimrc file, restart vim and try again. Repeat, trying to narrow down the region that contains the problematic command(s). Commenting-out lines works instead of the :finish command, too. You can keep your .vimrc file open in one Vim while restarting a different Vim to make the whole process go a little faster.
vimorgvim? – Benoit May 28 '11 at 14:21