I downloaded the Django Templates bundle and it works fine, but I have to select it as the active language on all of my template files. I would rather just select "HTML" as the language and have the Django Template stuff be included within HTML, just like PHP, Ruby, and Smarty are.

I took a look at the grammar and tried a few things, but was unsuccessful at integrating them. Could anyone give pointers on how that integration should work or, better yet, a working HTML grammar that includes this change?

It's not really a workable solution because the various languages start to conflict pretty fast with each other. The same basic constructs are used in the various languages.

As for selecting the language you only should have to do that once, after you change it once it remembers that choice for future files with that extension. Of course this changes all your .html files; best to use a different extension in Django because of that if that matters to you.