Chromium and VLC can’t be run as root. On backtrack 5 with default user root u need to make little modification to these applications.

Chromium
1. cd /usr/lib/chromium-browser
2. hexedit chromium-browser

u will get

3. press tab (once) to switch to ascii mode instead of hexa mode.
4. Ctrl+s to search for geteuid
5. modify (replace) geteuid to getppid
6. Save changes by pressing Ctrl+X

VLC

1. cd /usr/bin/vlc
2. hexedit vlc

do the same steps above
thanks to sumit