permissions - Unable to Write to Mount Applied by fstab

I'm having some problems mounting samba shares through fstab. The problem I'm having is that I cannot write to the share unless I am root. I've tried changing the permissions to 777 and changed ownership to myself. However, every time it's re-mounted, the permissions get reset to 755 and root ownership.

There is no writing problems when writing from another Windows-based PC, so I'm led to believe this is something I'm doing wrong. For record, here is my fstab entry:

//192.168.1.105/G       /media/downloads        cifs    username=Administrator,password=PASS,iocharset=utf8,sec=ntlm   0       0
//192.168.1.105/M       /media/media    cifs    username=Administrator,password=PASS,iocharset=utf8,sec=ntlm   0       0

The two drives in question are NTFS. I have tried adding dir_mode=0777 and umask=000 beside the iocharset, still with no avail.

Is there something I am missing here?

Thanks!