How can I watching TV shows and movies from Hulu or Netflix while being offline on my iPad or Nexus?
Netflix just released an iOS app that allows downloading of some content. Not all content is licensed for any country and some countries have no licensed content. As the licensing gets unified - expect more of this in the future.

Before the recent change, for a long time, both the netflix and hulu terms of service state that these are streaming services and not download services.

Netflix is at https://signup.netflix.com/TermsOfUse

Scroll down to Limitations on Use


  You may not download (other than through page caching necessary for
  personal use, or as otherwise expressly permitted by these Terms of
  Use), modify, copy, distribute, transmit, display, perform, reproduce,
  duplicate, publish, license, create derivative works from, or offer
  for sale any information contained on, or obtained from or through,
  the Netflix service, without our express written consent.


Hulu is at http://www.hulu.com/terms and it has a list of things that are not allowed. Including in the prohibition of:


  removing, disabling, bypassing, or circumventing any content
  protection or access control mechanisms intended to prevent the
  unauthorized download, stream capture, linking, framing, reproduction,
  access to, or distribution of the Hulu Services.


Whether these agreements are legal or violating them is illegal is something for the local courts, but it's clear you should not expect to use these services to download or time-shift the content. At the moment, your iPad can rent or buy content for offline viewing and Amazon also has a decent selection of downloadable content.

Additionally, you can usually rip CD/DVD you own with software like RipIt for offline viewing. Most Mac these days ship without optical drives, so you can still rip using either Remote Disc or using external USB drives.