To determine the HTML-Title for the created HTML-Files (the text between the <title> and </title> tags), rtftohtml looks for the \title-token inside the \info-group of the RTF-File. Thus you should give your RTF-Documents a short, descriptive title in the respective dialog box of your word processor (should be called something like "File information").
Another way to specify the document title is via the -T command line option. For example:
rtftohtml -T "My work of art" art.rtf
Note that this title will also be automatically inserted by rtftohtml into the first created HTML-File as a level-1-heading. That's why you should usually delete the very first heading from your RTF-Document (or at least assign a different paragraph format to that line) and use it as the document title. The reason for this is to prevent rtftoweb from interpreting the headline of your RTF-Document as a level 1 heading, where it should split.