line-wrapped to 120 columns

Why 120? That's not a very common size. Pick 80 instead. This is, of the screens with a fixed size, by far the most used. If the HTML is clean, 80 columns will not be a problem, if the indent is small enough. I prefer 2 spaces for HTML, 4 for code.

This said, I think one thing is severely wrong with your post. Quality is FAR more than just style and correctness.

There are some important issues you say nothing about. Pick a scheme for consistent class/id naming, and stick to it! Begin all script variables with 'x', to avoid clashes with elements in MSIE! Make sure everything works in Gecko! Define a scripting style! Etcetera! :)