In case you're having problems with the chat window itself you should go straight to the Parachat home page and click on the "FAQ" picture.
1) Type the following command :
* beep onMake sure you press the Enter/Return key after typing that.
This will make your computer produce an audible sound (never heard it myself, so I can't say what it sounds like :-) ) when someone else comes into the Chat Room.
2) Open a new browser window (usually done with the File menu's "New Window" or "New Browser" command). It'll start another session of the chat room, which you should cancel out of, and go browse whatever other sites you want to. In the meantime, your original browser window is sitting patiently in the chat room waiting for someone else to come in. When they do, you'll hear a noise, so you can switch back to your original browser and start chatting !
Keep in mind that the chat software will automatically disconnect you if you don't say anything for ten minutes, so you should pop in occassionally and type something.