Actually file extensions were used because of the limitations in the original FAT file system used by DOS. In other words... it had nothing to do with making it easier for users. In fact, Windows by default hides the file extensions.. So yes.. there is rubbish in there but you are spreading it as well. Unix (MAC OS X based on) was already using "magic" numbers that were embedded into the file itself to determine file type. This was a far superior method for assigning file types. Lets not forget the ol'crappy limitation of the 8.3 filename structure.
You wanna go farther... wth is up with batch files? Microsoft is more than capable of implementing a decent procedural based scripting language but they are still stuck with the old batch. Oh even better... why is that most windows applications cannot/or do not take in command line arguments. Even tiny little notepad.exe takes at least a file name.
Do you want to continue to process management... how about provide a seperate protected user space for processes to protect the rest of the machine? Linux, UNIX, OS2 Warp established that a decade ago...
As I said.. got a whole book full.
Looks like it had 1 button too....
http://sloan.stanford.edu/MouseSite/Archive/patent/Mouse.html
Sheesh dude.. it is a mouse.... you wanna keep going about the deficiencies of various Microsoft design.. Drop it already. If that is Apple's worst.. then they aren't doing too bad. How much of vista's interface was inspired by Mac OS X? ( I actually like Microsoft's keyboard the best)