I haven't tried any other operating mainly because, while I'm computer-savvy enough to do a lot of things with Windows, I don't have a DSL for downloads, I don't know how to partition hard drives or use commands, and my current hard drive is only 80 gig.
Despite what some people think, operating systems are a personal choice. I don't like Vista because (among other things) it gives MS too much control over what I can do with my computer, its licensing terms suck, and it costs too much for the relatively small improvements (at least useful to me improvements) over XP. That doesn't mean that everyone should feel that way or who what to change operating systems. (I happen to like XP. I think with proper tweaking, it's a fine OS. It's Vista I have real problems with.).
I like unix/linux style systems. Of course, I've used them on and off since the mid-1990s and learned to use a command line with computers in the 1980s.