There are several freeware scripts to disable right-clicking on your images. Here's one:
No Right ClickNot a guarantee, of course. I've read several times that if you don't want the image taken, don't post it to the web.
If it's not a huge deal, post them where you make a little money - Share A Pic. Pardon the plug, but if you decide to use them, please click on my referral link below and sign up.
http://www.shareapic.net/ref.php?owner=ThurstonNobody's going to get rich using this service, but I'm using it to cover eBay fees. After 1 month, it's covering about 20%.
FWIW,
Thurston