I use
Codelobster PHP Edition.
It's the best
free HTML/PHP/CSS/Javascript editor if taken all round.
Besides of standard highlighting and autocomplete for PHP, HTML, CSS and JavaScript it has pair tag highlighting, easy navigation through tags, preview in all browsers, hot keys for marking tags' content, attributes and its value.
Tooltips for images in code should be also noted, as the ability of navigation through the links with Ctrl-key holding.
It also includes special HTML code inspector, that allows to compare visible element with the lines of code, that are in charge of it (as in FireBug).