Source for DVD Downloads

I know, I know, this is not about AUDIO but someone probably has a good answer . . .My wife is looking for a good source to download movies. We have learned that encrpyption software for ripping or downloading DVD's is generally illegal but perhaps there is a good legal source for movies - free or otherwise.

Thanks for any suggestions. She wants to use her Windows Vista Media Player program.
Netflix (they have a view online version) and Amazon Unbox come to mind. Of course, iTunes works well also. I'm assuming you're looking to watch on the computer. If you're just looking for free TV, consider Joost as well.