cygwin emacs characters

I am running emacs from cygwin but am getting some strange characters appearing when using a shell. I assume this is something to do with the character set, but do not know why it is occurring. Anyone able to help ?

Running latest version of cygwin on windows xp

here is sample output from a 'shell

]0;~
bhuckel@wbkdwbhuckel ~
$ ls
_emacs emacs-21.3
]0;~
bhuckel@wbkdwbhuckel ~
$

all ideas greatly appreciated
thanks