Thanks for re-uploading some of Nermal Cat’s WNR videos! I liked using their startup and shutdown sounds for an old laptop of mine that runs Windows 98 and XP. In fact, I’m using their Windows 98 Service Pack 3 sounds right now!
2:43 IIRC, as is, the real sounds will be used as Windows XP due to the fake Longhorn sounds. it came from a Windows XP theme called Royal Noir. And the "startup" sound heard there was the shutdown sound on the original theme. While the fake Longhorn sounds are often said to have originated from Vista Inspirat 2, I'm pretty sure they have further origins. The reason why I believe this is due to them dating back to mid-2003, along with Vista Inspirat 2 lacking a couple of these sounds (if I'm not mistaken). Another possible origin is a transformation pack called Longhorn Refined. However, that appears to have vanished off the internet entirely so there is no way to verify that it even has those sounds.
Actually, there is a Windows 4. In Windows Chicago, on the setup, it tells you to title a floppy disk, in case that Windows Chicago doesn't boot up. So Windows Chicago is Windows 4.