Disable the right click
http://www.dynamicdrive.com/dynamicindex9/noright.htm
but it won't prevent people from saving your pictures.
If I Turn Right Click Off Doesn't That Stop the Theft?
Nope. One easy workaround (in Microsoft Internet Explorer) is to use File/Save As. This will
save the entire page, including all HTML and all referenced graphics and even adjust the HTML
graphic references so that it refers to the folder containing the saved graphics!
Another workaround is for the user to just go to the folder on the browser computer where the
browser stores all these graphics and get them from there. (This is commonly called the browser
"cache".)