>There's a lot of crazy that goes on in a desktop OS that must be cruft left over from legacy.
I agree with you but it depends on what you mean by cruft. There aren't really any windows features that actively consume (noticeable) resources and are not useful to someone. Designing feature rich software for a billion different usecases is quite hard. Its reasonably easy to make one-off products that just do one thing well.
> If you put a bad CD in it you can lock the whole window manager up while it's thrashing the CD to be head or tales of it. Sometimes crash it. As soon as you hit the hardware eject it will free back up.
Wow.. are you running Windows 95 ? :) The CD thing was common back then. The only reason this can happen on NT is because of some really buggy driver/hardware combination but even that is highly unlikely. Whats far more likely is you have some kind of buggy explorer plugin that is attempting to generate helpful thumbnails or something while enumerating an unreadable medium. AFAIK Explorer is still single-threaded for the most part for backwards compatibility - which worsens the impact. (Unfortunately a lot of this crap is preinstalled by the OEM) IMO Microsoft made an enormous mistake by allowing third parties to extend their OS in ways that can seriously impact user experience like that. Learn from Apple, MS !
>There was the post on HN some months back about the tickrate in windows being set by random applications super low and not being put back up so it uses lots of extra power for no reason.
Are you talking about timer coalescing? I believe you cant change that setting without a reboot. Or perhaps you mean something else.