Don't say it's the shittiest, I had Win2k, it's a very good operating System: But WinXP Pro runs more stable for me. My average uptime is 7 days (mostly restart because of power going out. lol).

When I still used Win2k sometimes my webserver hanged, but other than that it had no problems.
WinME on the other hand.. Ack I never saw my desktop (covered by blue screen).

And worst OS ever is Win 1.0. I doubt any of you know what it is, but I am glad. That thing should have never been made!

And I disabled my Indexing service a long time ago, because I never search for files and thought how to make this heap of junk faster.