That won't work. All a scraper would have to do is just type out the content, or use a program to copy it for them. Seriously, you want to protect your files, either don't put them online, or password protect them. It's really the only way.
If you're providing a live demo there is always a way to pull or steal it, regardless of encryption. Your best bet would be to put a watermark on all of the images
that's great for proving that you are the owner of the images. but what about the source code? It's like you said, there's always a way to get it.
PHP - Make a php page somewhere that echoes all the html out. (use external css/script and local images) Make a page in php that includes the aforementioned page, this will be public. If you do it right, no one will be able to tell where the original came from, hence protecting at least your local css and images.
An HTML website is like a billboard. If someone can see it, they can take a picture of it and it's their's forever.