The best OS I've used is still OS/2 in the context of its time. If development had continued, it would beat the stuffing out of Windows 2k.
Windows is not MY choice - it's the only viable choice for a real world business - for reasons that are ugly and unjust, but I didn't make the rules.
Linux could STILL be a great personal thing if IBM would put its back into it, but they really have no business reason to do that apparently. Still, with all the resources they have, why not do it? It's a mystery to me. I participated in the APL2 for Linux beta program, and from that it was clear that workstation Linux at IBM is a fringe effort right now.
Linux/UNIX is STILL a great server OS because it has very fast and stable I/O. A workstation OS needs more process granularity though.
Yes, I loved Linux once. What a rush to have personal UNIX for free! Things changed somewhere - I got disillusioned. Basically I realized that it is no more stable in practice than modern Windows, and just as difficult if not moreso to maintain. I spent too much time tweaking things and not enough time making things.