Menu page textBrowser Info Environment
You can add translation file (mo) in the theme and translate "Menu" to whatever you need.
second option is to edit the files in the theme.
in every file find line 7 - 8
<div id="menu_title"><?php echo t('Menu')?></div>
and replace that 'Menu' with whatever you need.
files to be edited :
right_sidebar.php, home_alt.php, home.php, full.php, blog.php, default.php
I'll make Russian translation then.