Another small tip, in case someone else wonders about this: it appears that you cannot change the default html editing program through the “Default Programs” tool in Vista (if you select e.g. MS FrontPage, it will also use FrontPage to open and show all html files, not only to open them for editing). I did find that you can set the editor by going to Internet Explorer, selecting Tools > Internet Options > Programs > HTML Editor. After that, your default “open file” action will be set as in “Default Programs” and the “edit file” default as set in Internet Explorer. (This is silly, btw — this kind of action defaults should obviously be set in OS settings not through settings of some single app, shouldn’t they?)
frans goes blog 
HKEY_CLASSES_ROOT\HTMLFILE\SHELL\EDIT\COMMAND
How mad is it that MS forces people to dive into the registry for such basic and simple mods? They spend all this effort in Vista on security and stopping users from tampering and then undo their own manifesto with this rubbish.