Quality of Windows apps are very poor except the few made by either Microsoft or by larger companies (but even they still use weird and wonderful installers). I think the biggest cause for that is the lack of development tools in the beginning without paying or pirating.

OS X provides a nice solution to both lazy developers and users but just packing everything up into a .app folder. No need for an installer. xCode is pretty epic, and it seems developers are using it to make decent apps.

Aside from that, I’d also like to make the point that most of your other points aren’t Windows fault. Take for instance the problems of applications having awful installation/removal programs and leaving support files everywhere. Both of these have been addressed in a Microsoft-supported manner (via Windows Installer and the Application Settings folder) since Windows 2000. It’s just that lazy/clueless programmers ignore them.

Really, what you’re complaining about mostly isn’t Windows… it’s lazy and clueless application programmers, which while Microsoft has had their fair share, occur everywhere.

Linux and MacOSX are perfect in my opinion. It’s just everyone else is locked into Windows which makes alternatives almost possible to use on a daily basis.