I think it depends whether you want to include Windows 2000 in the discussion. It was solid and I used it until XP came along but it was built on NT and marketed as more of a server option. I don't remember it ever being included by OEMs. I think most people went from 98SE (or god forbid, ME) to XP. I think its popularity and driver support probably led to XP but in a canonical list of MS consumer operating systems I would probably skip 2000.
It's very evident from the context that we're talking about shifting gears, not shifting between different ratios
What, you don't think it's reasonable to watch two minute-long HD ads to watch a trailer for another product in standard definition?