A Dream Guide is essentially a dream character or some manifestation in your dreams that can help you in any number of areas of dreaming, be that exploring one's own mind or helping with dream control, etc. I have no experience, so all I can offer is hearsay, but there are some who believe that DGs can be either from one's self or something external that "visits" one's dreams, so to speak. Others believe it's just a manifestation of one's mind. Some take a more spiritual view of who/what DGs are, and others don't. It just depends on what point of view you're looking from.

Now, as far as the DV DG program, our job is to make new members feel welcome, offer answers and/or opinions to dream and LD-related questions, and in general be available to help out when members are stuck.