OS X :: Permissions Screwed After Time Machine Restore

I recently used Migration Assistant to make my new machine like my old one via TM. Now, all the permissions on more or less everything are messed up, and I can't change anything without going into Get Info and adding myself. I do not want to do this every single time I want to update an Application, for example. How do I do this "globally"- give my administrator account Read/Write permission for all of the normal things?

So far I have tried this: [URL]
Which did not work and returned this error:
Code: $ sudo chflags 0 /Volumes/Macintosh HD
sudo: can't open /private/etc/sudoers: Permission denied
I tried this: [URL]
Which resulted in this:
Code: $ sudo chown -R miles:staff /Users/miles
sudo: can't open /private/etc/sudoers: Permission denied

Why am I being denied permission using sudo? It doesn't even prompt me for my password. And now after restarting, I get stuck on the blue loading screen.