You cant hide your source code..there are ways to make it less visible, but its impossible to completely hide it.

As for having images and text stolen, if you're the one that made the images and text, then you are legally the copyright holder by default, and they are stealing your content.

Have a word with the website owners who have published your content saying that it is your content.

Although in what way are the images and text stolen? You dont have to look at the source code to save images and text from a website.

:)

You can watermark all your images with your domain name. If someone republishes them, at least the viewer will know that they came from you. The watermarks can probably be removed or covered up by someone knowledgeable in Photoshop, but if they want to go to that extreme there's probably not a lot you can do anyway other than pursue legal action.

To help deter the removal of a watermark use a transparent layer with a multi colored gradient fill.

Please don't fall for any software that claims to protect HTML pages and images as it simply doesn't work if it can be loaded into regular browser without any special plug-ins or client side applications.

Make the watermark very very dark and as large as possible, so its obvious that you are serious on the issue and have had problems in this area.