How can i recover data from a Macintosh HD with Linux? Or something else?

I have a Macintosh HD that wont boot but the data is there. A media distro of Linux called GeexBox or something like that can see my media files and access and play them, but Unbuntu linux cannot access the files because i do not apparently have permission. I know i used a pword with my account on the Mac so i'm uming that's why but I want to know how i can salvage my files like GeexBox can see them, but theres no way for me to transfer the files anywhere else the way the interface on Geex Box is, can anyone ist me? THanks!