As a humble "end user" -- sorry if what I say might seem dumb or naive-- what I like and want is an easy to 1-find, 2-isolate, 3-backup and 4-recover, configuration/settings file. And I wish there was a unique convention for the way settings are stored. But, too often, it seems like a melting pot of registry settings, .INI, XML or LUA in the program folder OR the user's folder. Personally, I hate the registry for storing settings -- to me, the registry, if any, should be for the OS only. I prefer the *n*x way, seems more secure too, as Josh said.
I very well know that MS Windows' registry main function is to organize in one place (since it's a database, basically) all the settings which used to be scattered all around (in .ini files or whatever) ... But it just doesn't seem like the right way to keep track of software settings anymore. Like some here seem to suggest, the same results could be achieved if all software settings were stored in the user's folder, in clearly identified files and subfolders + in the program's installation folder ? It might use a bit more HD space (but it's less a problem nowadays), but it would be sooooo much easier to backup and restore individual programs' settings** and would insure that everything is portable (I guess I agree with ethyar and josh). No?
**I don't know any easy way to save software’s settings when stored in the registry. And I don't think I'm alone in that (especially since I'm basically an end user, not a programmer): "Restoring parts of the registry is hard because the user cannot easily extract data from backed up registry files. Offline reading and manipulation of the registry (for example from a parallel installed Windows or a boot CD) is not trivial" (wikipedia). BTW : Is there a quick way for a normal user to backup only ONE software with all its registry settings (and only it's own registry settings, not the whole registry), and only restore that software with its settings ?