How about Notepad? For half of my first decade as a programmer, I wrote my HTML and ASP using nothing but Notepad. Even nowadays, I do the majority of my work in the Code view of whichever IDE I am using. There is nothing wrong with this; it is often the only way to create truly optimal code. It would be feasible to code pages using your favorite text editor, but there are many tasks, such as laying out your Master Pages, Web Part Pages, or Layout pages, where a WYSIWYG editor is necessary. In any case, much of the raison d'être for SharePoint is to allow content creators to easily add pages to their site, so let's not make things difficult for ourselves by choosing a tool that is too basic.

Visual Studio 2005 then? It is brimming with features and can be a good option if you are a developer, as you almost certainly already have this product and will be familiar...