<enter> button function

It's just that way in OS X.

 

The command+o to open programs makes sense if you think about it this way... all the file commands on a mac start with the command key

cmd+c = copy
cmd+v = paste
cmd+x = cut
cmd+delete = move to trash
cmd+i = file info

if you look at it that way it is quite consistant

 

Is it nonsensical for any reason other than it's not what you're used to in some other operating system?

 

No, it's nonsensical to have enter open things and CMD + ... do everything as. As Paul puts it...

 

You sir deserve a hero cookie.

 

Instead of insisting that OS X does it "right," I'm going to try to help you change it...

Go to System Preferences and type "Keyboard shortcuts" in the search field and press Return/Enter. This will bring up a list of shortcuts that you can configure to your liking.

 

If he wanted to be really cool he could make it CMD + OPT + ALT + SHIFT + DEL + O + Z

As a side note, this is moderately related to this discussion.

 

Aren't opt and alt the same

 

That's the cool part - you have to release that key and then press it again without releasing the other keys in order to trigger the command.