If you want to post copyrighted material such as maps and player handouts, you'd be in violation of the Berne Convention if you did.  The only fair use here in the US (UK law may differ) is a couple sentences or perhaps a paragraph, if used solely for the purpose of review or critique.  Maps and illustrations are not subject to fair use, although you CAN create your own version of the map that others can look at, since ideas are not copyrighted, only their expression.  Yet, these legalities do not stop some from posting entire rulebooks for download on the Internet.

Describing what the characters do during a module, as well as describing the contents of the room in your own words is perfectly acceptable and in fact is protected by copyright the moment it is posted.  However, if you are simply reading from the module, then you'd be in breach of the Berne Convention.

Password protecting a web space simply to avoid copyright infringement would be useless unless you yourself were the only one able to see it.  If even ONE person outside of you can see the digital copy of the work in question, then you have committed copyright infringement.

My advice?  Draw your own maps.  Rewrite the text of the player handouts in your own words.  Then post it all.