I always do it with Frank Bültge’s Adminimize
- in Global Options, you’ll find Your Own Options
- in the left column you put any name for your reference
- in the right column you put the ID or Classes you want to hide
- if I’m not mistaken, you’d want to hide this
#visibility.misc-pub-section,.misc-pub-section.curtime.misc-pub-section-last
Here’s a reference list of mine with examples and a screenshot… you can go pretty wild and hide a whole bunch of stuff, and select what to hide according to user roles, it’s just a matter of using Firebug or any Inspector and you’ll end up with a minimalist admin.