if it's on the net then then people will always be able to copy...if you really don't want people to copy then don't put it on the net in the first place then no one can copy..lol you could watermark your images also...it doesn't stop copying but it's something
a quick search in google on "stop people copy from my website"[url=http://www.jamesshuggins.com/h/web1/how_do_i_stop_downloading.htm]got this as first result read it[/url] it explains how the web works