a html to txt converter ( for converting bookmark favorite html exported files)

Can't you just rename the extensions?

a html visual editor(does one exist?)

You mean a WYSIWYG editor? There are many; for example, Netscape Composer is included with the Netscape browser. A list of some is on this page of the Google directory.

a "whats-the key code for the character I want" utility(does one exist?)

In Windows, the Character Map: Start » Programs » Accessories » System Tools » Character Map