help with some basic osx terminal commands. fixing permissions on NAS share

I'm hoping someone here can help me. I'm computer literate but by no means an expert! I'm simply trying to recover data from my DLink DNS343 NAS mounted on my X86 iMac using SMB. Somehow, in moving to a new computer, I have lost access to some files on the NAS. Just some files are access denied.

After 6 hours of research, I think what I am supposed to do is fix the permissions on the NAS. The option to change them via the finder is not there in this case. It simply says "No Access".

So i think what i need to do sounds something like the following:
Use terminal to get root access to the SMB NAS share.
Execute chown and make me the owner of all folders and files
Execute chmod and change all files and folders to 777

Then I can hopefully access all the files and get them the heck off the thing and use an external hard drive like every other average joe who doesnt know how to work a NAS.

If anyone can help, I would appreciate it SO MUCH. The NAS currently stores all my family videos, photos, etc etc.
:confused:Thanks!