As far as I understand your question, you want to provide your website as demo. In this case you will provide a link in your website and once it is clicked a download through FTP will be started.
If this is so then you can zip your complete website so that it can be downloaded at once and to encorporate FTP consult the following article:
An FTP client library for .NET 2.0[
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Or for a complete list of other articles on the same use the following:
http://www.codeproject.com/info/search.aspx?artkw=ftp&sbo=kw[
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