Copyright protects someone from copying your media -- whether it be text from a book, a recorded song, etc.

A Patent is for a new way to make something like a business process, or a new thing itself like a new type of light bulb.

If you simply have an idea for a web site, you should just work on it yourself to get it as far as possible and then bring in other experts. Like another poster mentioned, ideas are relatively easy to come by. Executing on that idea to actually create something that people want to use is the hard part.