This addon allows user to easily grab and save:
- large version of all images from the album page (NOT originally uploaded ones),
- songs from the songs page.
It is anticipated that this addon may break due to site layout changes. If it doesn't work for you, make sure you're using the latest version and if latest version is also broken, report this to the author.
P.S.: If you like VKGrab, try VKMail, threaded mail for VKontakte: http://userscripts.org/scripts/show/58463 (you will need to install Greasemonkey first - https://addons.mozilla.org/ru/firefox/addon/748)