Hey Folks,
Though there are indeed several ways of disabling the right mouse click button, you will find that allot of people use the right-mouse button as it was designed (for example for the functions: Back, Forward, Create Shortcut, Add to Favorites, print & refresh).
The people on the other hand who want to lift your images, usually will be people who are IT-literate enough to just lift the images from the 'Temporary Internet Files' IE so nicely keeps for us.
So in other words, though it is possible to block the right mouse button, one can still find the code (and so the addresses to manually download the images), and the actual viewed images from the 'Temporary Internet Files'. So you are actually crippling the experience for the person just trying to use your site, and not actually achieving anything.
We never fail, we just find that the path to succes is never quite what we thought...