I've been using Windows since 3.0, even if it wasn't my first choice. Sitting in front of Windows XP, i happened to notice something i'd not seen before. I had a long running task - consuming CPU time. The interactive response had become crappy, even though the machine is generally pretty capable and modern. I brought up the task manager, and found my program in the Processes tab. On a whim, i right clicked on my task. A pull down menu came up. One of the entries is Set Priority. There are six entries, Realtime, High, AboveNormal, Normal, BelowNormal, and Low. There was a bullet by Normal. I set it to BelowNormal. My interactive response snapped back to reasonable. And, the task seemed to be getting most of the wall clock time in CPU time, as i'd wanted.
Now, i could rant about how under Linux, or other Unix variants including MacOS, the normal priority for a CPU bound task does not, in general totally mess up interactive response. It's just under Windows. I could also rant about how right clicking on random data is not a particularly discoverable user interface. It's not like my employer gives me a Windows manual to read, or the time to read it. I can't very well right click on every little piece of data in every window. But at the moment, the fact that there's a problem i can actually fix, and easily, is a good thing.