1. The simplest and easiest is watching tv and movies on the internet legally from the network's own website or another 3rd party website:
you name the network and they have a website where they will playback new episodes for free with limited advertising online.
http://www.tvsquad.com/2006/10/01/where-to-find-your-favorite-shows-online/
3rd party sites with and without ads:
hulu.com
veoh.com
youtube.com
http://www.primetimerewind.tv/home
beelinetv.com
If you do not like the quality of the online experience, there are other great was to watch tv with out paying for cable monthly: